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Talk:Y-chromosomal Adam

Other male contemporaries' non-patrilineal descendants
The edit stating "His other male contemporaries also have descendants alive today, but not, by definition, through solely patrilineal descent" should not be changed to "could also have." Either form needs a citation, ultimately, but the form without "could" is logically certain. First, since Y-chromosomal Adam, by definition, has descendants, so do at least one of his sexual partners. Since at least one of these has descendants, so too does her father. Therefore, one or more of Y-chromosomal Adam's father(s)-in-"law" (no known law at the time) has descendants. Even if that "father-in-law" is also "Adam's" father--partner being sister, that's still a non Y-MRCA man who is a contemporary ancestor of humans. Second, and more importantly, Y-chromosomal Adam existed long, long before the identical ancestors point. Any human who lived before the identical ancestors' point either became an ancestor of everyone living today, or of no one living today. As humans do not show a population bottleneck of 2, but rather of ~10,000, there must have been many male contemporaries of "Adam" who are not only the ancestor of some, but of all humans. I agree that a citation would make this better, but please note that this is not WP:OR any more than deleting the "could" is WP:OR Satyadasa (talk) 04:56, 9 October 2014 (UTC)

Descendants of Adam and Eve
In the article we read: "While their descendants certainly became close intimates, Y-chromosomal Adam and mitochondrial Eve are separated by tens of thousands of years." I have a hard time understanding why "their descendants certainly became close intimates". If it is true for some mathematical reason or based on some genetic evidence, it is not obvious to a layman (like myself) why it should be so. Couldn't Eve and Adam have been from two separate and isolated communities that merged only much later but men of Eve's community left no strictly patrilineal descendants and women of Adam's community left behind no all-female-line descendants? I might be missing some obvious point here. Otherwise, it would be great if the article cites a reference for this sentence. Smirarab (talk) 03:24, 20 October 2010 (UTC)

Regarding this statement in the heading: "However, unlike his biblical namesake, the bearer of the chromosome co-existed with other human males and was not the only human male alive during his time." There are Biblical scholars and others who say that Adam might have been created by God even though there were other humans already on Earth. This would explain the Cain's wife conundrum, for example. Shocking Blue (talk) 22:38, 12 March 2013 (UTC)

Y-chromosomal Aaron
Now we have Y-chromosomal Aaron -- those interested may wish to comment on the vfd page. Dunc|☺ 10:43, 22 Oct 2004 (UTC)

 * We've had this article for quite some time, and despite skepticism - the phenomenon is there. Vfd has been withdrawn, by the way. JFW | T@lk  14:12, 22 Oct 2004 (UTC)

 * I do not support the deletion of the Aaron article. It strikes me as one of the crankier things in Judaism, but it's fair enough to give it its article. I do oppose the linking of Aaron from here. "Y-chromosomal Adam" is just a pet name. It has nothing to do with Genesis. "Y-chromosomal Aaron", otoh, is completely arbitrary, we might as well have "Y-chromosomal Smith" tracing the common ancestor of all people called Smith. this link says "The name Eve, in retrospect, is perhaps the worst possible name to give to the entity in question" for mitochondrial Eve. The same might be said for Y-Adam. It was chosen as a funny and suggestive name, without thinking that it may stir interest in religious or racist circles. Y-Adam is significant and interesting to trace the origins of humanity. Y-Aaron may or may not be of interest to questions about the jewish diaspora. A link from "Aaron" to "Adam" is in order, in the interest of making clear the concept. Nothing is gained by the link from Adam to Aaron than to shed a dubious light on the whole thing altogether. dab 13:04, 7 Nov 2004 (UTC)

Dab, if you can come up with with a better name for this article then please do propose one. As for Aaron, it is cranky indeed, but the proof if quite interesting. Furthermore, both the Adam and the Aaron research employs the same methodology and linking Aaron from here is interesting for the sake of comparison. BTW the Aaron phenomenon is also quite forceful proof that the wives of the kohanim have generally been faithful to their husbands :-) JFW | T@lk  13:12, 7 Nov 2004 (UTC)

 * fine. at least, let me move "Aaron" to the end of the see alsos. Oh, and I don't suggest we rename "Adam" to something else. It's what it's called now. It may have been an unhappy choice, but we're stuck with it now. dab 13:16, 7 Nov 2004 (UTC)

Cool. JFW | T@lk  20:18, 7 Nov 2004 (UTC)

Actually the Aaron phenomenon shows that when the wives of the kohanim have cheated, it's usually been with another Cohen. Which makes sense, considering the high status of kohanim in Jewish society. --60.240.145.232 (talk) 07:56, 1 August 2011 (UTC)

FINDING OUR LINEAL ANCESTORS
I have one question to ask.

Since men have XY would it be correct to assume we can trace his mothers maternal line and his fathers paternal line

AND

Since women have XX would it be correct to assume we can trace her mothers maternal line and her fathers maternal line?

From: Australia. 15/01/06

 * Yes, you can trace a man's maternal line, not because he has an X chromosome, but rather because he has his mother's mitochondrial DNA. The same is true of a woman, but you can't trace a woman's father's maternal line on the basis of her own DNA - to do so you need mitochondrial DNA from her father, his siblings, descendants of his mother via maternal lines, or some other suitable candidate. - Nunh-huh 17:57, 22 August 2006 (UTC)

age
90.000 years, fair enough. But 35.000? whose estimate is this? This would be significantly younger than e.g. immigration to Australia or the Americas. This would imply that there have been some *very* mobile males during the Neolithic that weeded out all earlier Y-chromosomes in these continents. dab 16:28, 5 Nov 2004 (UTC)
 * since nobody answered this, I did a websearch and came up with the figure 60,000. I don't have any hard evidence to back this up, but I insert it for the moment, as it fits human migration much better than th 35,000 figure. dab 13:14, 7 Nov 2004 (UTC)

From Hammer, 1995: "The time back to a common ancestral human Y chromosome is estimated to be 188,000 years, with a 95% confidence interval from 51,000 to 411,000 years." Abstract --Astator 11:24, 25 April 2006 (UTC)

hypothetical?
what is this "hypothetical"/"If such a person existed" business, btw? Y-Adam existed by definition. It may not be possible to identify him positively, but if we define him as the mrca of the Y-chomosomes present in the world population alive today, this defines a particular man who must have been alive at some point. Why hypothetical? If I define "dab**100" to be my father's father's.... father, 100 generations removed, that doesn't make dab**100 a hypothetical figure. rather dab**100 is uniquely defined, even if I cannot tell you his real name. ("mrca of the Y-chomosomes present in the world population alive today", otoh shows that Y-Adam is defined relative to a particular time. I.e. 2004-Y-Adam is not necessarily identical to 1800-Y-Adam (in all probability he isn't). Y-Adam may even change overnight, i.e. if the last bearer of a particular Y-mutation/male line were to die. If nobody explains how Y-Adam is hypothetical, I will rephrase the article according to what I just said. dab 15:23, 7 Nov 2004 (UTC)

 * 2004-Y-Adam is probably identical to 1800-Y-Adam, given that world population has risen so fast and there have been relatively few extinctions of long-lived subgroups. Since the individuals concerned cannot be indentified, all you are left with is a definition and a time estimate: the definition alone does not even guarantee that Y-Adam was human. Some people would call this a hypothetical man based on a hypothetical definition.  --Henrygb 17:46, 24 January 2006 (UTC)
 * it's hypothetical alright, but the 'long-lived subgroups' are not the groups responsible for the population rise. The groups with the longest isolated Y chromosomes are likely stone age people in Papua or African Bushmen, and it is not unlikely that there are a few single indivduals in the jungle somewhere with whose deaths the date of Y-Adam will be postponed by millennia. We just don't know. dab (ᛏ) 08:45, 21 March 2006 (UTC)

Creationism
needless to say, the creationism stuff was offtopic; it is still correct to say that in a biblical literalist's world (not just "Creationism", that's not the same), X-Eve is certainly Eve, while Y-Adam is certainly later than or equal to Noah. Therefore even in the intellectual prison of Christian fundamentalism, the concept that Y-Adam has never met X-Eve is perfectly admissible. I find this amusing, since after all Y-Adam was named after the Genesis character, and it might make sense to point out that it would have been more consequent to name him "Y-Noah". dab (ᛏ) 08:41, 21 March 2006 (UTC)
 * Damn you for getting in first! :). I presume we can check the relative dates of X-Eve's various daughters against that of Y-Adam to see if Shem, Ham or Japheth had more than one wife each?
 * More seriously, has anyone come up with a statistical model which could determine how small a population would need to be to yield a 50%, 10%, 1% or even 0.1% probability that only one male line (or female line) would survive? Koro Neil (talk) 02:52, 19 January 2009 (UTC)

I agree with both of the above. If you're going to use a biblical allusion to talk about our genetic common male and female ancestors, you might as well show a little expert knowledge of the Bible, which says that our last common male ancestor lived many generations later than our last common female ancestor. It should be 'Y-chromosomal Noah' and 'Mitochondrial Eve'. For the second point, I am extremely curious whether anyone has actually worked out the probabilities of only one female or male member of the population leaving behind any descendants after so many millennia. To say, for instance, that it would only take one daughter-less generation after each of 'Eve's' contemporaries sounds misleadingly straightforward. Think about it. If each of her contemporaries had had no daughters, that would be improbable enough. But then if you accept that many of her contemporaries would have had some daughters, then you require ALL the daughters of ALL those contemporaries not to have any daughters. Do the same operation for the following generation and so on, and you get to see the problem. It gets exponentially more and more improbable with each generation. Now, of course bottlenecks happen, which would seriously constrict the genetic variation at the time the population is reduced, but from the scenario I sketched above, if mitochondrial variation still existed in any form, the only kind of bottleneck that would under any reasonably probable scenario eliminate all other variants would be a bottleneck of one female. Basically, as far as I can see, the only scenario that makes sense is that, because of whatever disaster, all or almost all other females had died by Eve's time.Jtgw (talk) 19:31, 2 October 2009 (UTC)

Human?
Would he necessarily have been human? --LakeHMM 23:24, 6 May 2006 (UTC)
 * strictly speaking, not a priori; in stochastic simulations, there would always be a finite chance that a paternal line dating to pre-Homo times (more than 3 Mya) survives, but this chance will be astronomically small. Similarly, empirical evidence seems to preclude this, but of course not every person on the planet was tested. When I say "astronomically small" I imagine a number like 10^-20, which is to say "we are sure he would have been human". dab (ᛏ) 19:23, 28 June 2006 (UTC)

 * Yeah, and then we hear about Albert Perry of South Carolina, who had hos male ancestry checked and caused a small furor because his markers weren't found.  After some diddling around, they found he descended through a small obscure group of people in west Africa who had never been tested.  This discover set y-Adam back about 100,000 years or more.  See http://www.dailymail.co.uk/sciencetech/article-2289492/The-family-tree-test-rewrote-human-history-Researchers-stunned-DNA-submitted-online-service-dates-338-000-years.html for a news article about it.  SkoreKeep (talk) 05:55, 13 March 2013 (UTC)

Noah?
In the sister article on mt-Eve there was an explanation on why mt-Eve can't be compared to "Noah's wife". The reasoning being that according to the tale about Noah's arch he took his wife, his sons and their wives with him. Unless his sons married their sisters, Noah's wife could therefore not be mt-Eve by analogy.

Does the Noah example work for Y-Adam nevertheless? All males onboard the arch would be his direct offspring, though the females (apart from Noah's wife) would not. I'm not very savvy when it comes to bible details (I never read through the entire Lord of the Rings either, though I found it more enlightening and relevant ), so it'd be nice if I could have some "authorative" word on this. — Ashmodai (talk · contribs) 14:38, 23 September 2006 (UTC)

 * Nice observation. Just from the biblical description you've written above, then yes, according to the bible, Noah would be the Y-chromosomal "Adam" until a later Adam came along after another male-bottlenecking event (or, for example, if only one of Noah's sons gave him a grandson, then that son would become he new "Adam".. Although the Y-chromosomal DNA would likely be indistiguishable from his father's.) For the record I never read Lord of the Rings either, except for the Hobbit, but then they brought out a movie of all the others so I never had to :) —Pengo talk · contribs 22:28, 23 September 2006 (UTC)

Well if we take this numbers serious and we take the bible serious and allow for certain room in the interpretation of the "son of" genealogy in Genesis and the six days of creation, we could assume that Eve lived before or is identical to mt-Eve and Noah lived before or is identical to Y-Adam. Which tells us not much, besides the flood must have been pretty long ago... —Preceding unsigned comment added by 88.73.9.154 (talk) 11:46, 29 August 2008 (UTC)

New external link
I added a link to, a diagram I put together. I think it will be helpful to people interested in this topic. JoeCasey 13:44, 18 January 2007 (UTC)

Myth!
Why is the creation according to Genesis listed as a myth when it is believed by many people, when a myth is not factual.

- Even though I DO think it's (along with religion) a myth, I find that calling it so is non-neutral POV. But I don't know how to reword it to not be biased towards either side. 24.68.65.244 04:30, 30 March 2007 (UTC)
 * please look up myth, religion and mythology and wikt:myth for the meaning of the term. dab (𒁳) 09:38, 30 March 2007 (UTC)

It should be noted that the biblical text would also suggest that Adam & Eve were not the lone humans in the world. The 'mark of Cain' had to be placed on their first born to protect him from others, Genesis 4:14. It is also quite possible from the subsequent text that Cain's and other descendants wives were not Eve's daughters. Therefore I don't believe there would be a biblical requirement to believe that Eve was mitochondrial Eve. As I understand it the biblical imperative is to believe we are descended from Adam and have part in his disobedience and consequent punishment, Romans 5:14. —The preceding unsigned comment was added by Dgpl (talk • contribs).

 * You are trying to make sense of inconsistent accounts of various bible passages, some borrowed from Mesopotamian myths and others edited by later generations. According to the bible, Adam and Eve were the only people God created, as explicitly stated.  If that were truth, Y-chromosomal Adam and mt Eve should be dated to the same time.  In fact, genetic Y Adam and mt Eve should be dated to Noah and (very possibly) his wife (there were only a few women left in the Ark).  And guess what, we should also find a population bottleneck for ALL animals that live today, at the time of the flood.  But unfortunately, that is not the case, scientifically.  So, I do not believe we need to further complicated things by trying to add more clarifications to this article.  Also check out the numerous first men and first women; why talk about the Christian tradition only? Fred Hsu 02:38, 21 August 2007 (UTC)

 * Noah's daughters-in-law were (probably) not descended from his wife. Koro Neil (talk) 03:08, 19 January 2009 (UTC)

Possible error?
The article currently says the following (emphasis mine): "The name may seem to imply that Y-chromosomal Adam was the only living male of his time, but he in fact co-existed with a large population of human males whose male offspring either did not survive to modern times, or who are ancestors of some, but not all, currently living humans." It seems to me that this needs to be corrected. By using the logic from the last paragraph of Mitochondrial Eve, every man living at the time of Y-chromosomal Adam is an ancestor of either none or all currently living humans.

That is, the contemporaries of Y-chromosomal Adam either have no surviving descendants, or are ancestors of all living people, but aren't connected to any of them by an all-male line. —Preceding unsigned comment added by 18.21.0.86 (talk) 18:17, 8 June 2008 (UTC)

 * I agree that this topic is potentially confusing to many readers -- particularly because of the misleading emphasis on "descended from a single man" -- and needs to be expressed more clearly. As our MRCA article explains, the human family "tree" is not tree-shaped, but a complex maze of interwoven strands. An MRCA of a particular population simply means an individual from whom a descent line can be drawn to all the living members of the population; it says nothing about other ancestors, and it is practically certain that many members of that population are also descended from other ancestors alive at the same time as the MRCA; it's just that it isn't all members.
 * Now, the Y-chromosomal MRCA is a special case, because unlike other chromosomes, the Y chromosome is also the whole gene for maleness, and isn't shared between parents. Thus we can say that any person exhibiting that genotype (i.e., all males) inherited their Y chromosome from "Y-chromosomal Adam." However that says nothing about any of their other genes. The very first line of our article brushes on this, but doesn't make it clear enough (in my opinion.) Later when we say " ...Spencer Wells has concluded that all humans alive today are descended from a single man ..." we really should emphasise that they are also descended from many other men who were alive at the same time; "Y-chromosomal Adam" is their MRCA only for the Y chromosome.
 * We should probably also mention that the estimate of 60,000 years ago is based on the molecular clock hypothesis, which is by no means universally accepted. -- Securiger (talk) 20:51, 17 December 2008 (UTC)

Graphical presentation
I'm reading this now.. and, IMHO, some graphical presentation of the concept would be good for better understanding. Something akin to a "family tree", maybe animated, showing lines being cut with a new Adam appearing? Best regards, -- C opper K ettle  20:09, 19 May 2009 (UTC)

Age?
"In scholarly literature first "Adam" or rather first paternal ancestor date was estimated at 270,000 years ago.[4][5] Later new set of markers was chosen and the age was adjusted to mostly cited value.[6] The dates calculated on new markers was 37,000–49,000 years ago [7] to 51,000–411,000 years ago [8]" - So does this mean that the first guesstimate was wrong or that the evolutionists pressured them to change their results to fit the establishments accepted theories?--Degen Earthfast (talk) 00:28, 18 September 2009 (UTC)

Recent findings on Neanderthal and Denisovan contribution to genome of modern humans
I put a question relevant to Y-chromosomal Adam at the Science RefDesk. It is important because it raises the possibility that Y-chromosomal Adam could have lived one million ybp. Mathew5000 (talk) 03:52, 18 July 2011 (UTC)
 * It's a possibility, but no evidence yet. If they do discover some extremely divergent Y-chromosomes or MtDNA then it would change the dating of Y-Adam or Mt-Eve, but until such a discovery these exclusively maternal or paternal lines must be presumed extinct.-- cheers, Michael C. Price talk 06:37, 18 July 2011 (UTC)
 * My understanding is that homo sapien y-Chromosomes have been molecularly dated to no more than 140,000 years ago. That means that *all* modern y-Chromosomes fall under this umbrella, in a sense.  If there had been any long terms surviving y-Chromosome mixing between archaics and modern homo sapiens, then there should have been  a ~500,000 year measurement of difference between at least some pair of human y-Chromosomes.  That said, a Neanderthal toe bone has been discovered in the Denisova cave (not a Denisovan, but a Neanderthal.)  It apparently contains a y-Chromosome (the others have not), so we will know for sure very shortly (probably end of the year latest). Qed (talk) 22:44, 12 April 2013 (UTC)

Name change
This is a proposal to change the articles name from "Y-chromosomal Adam" to "Y chromosome Adam". Wapondaponda (talk) 07:19, 24 July 2011 (UTC)
 * No: -- cheers, Michael C. Price talk 07:57, 24 July 2011 (UTC)
 * lol. Yes when it comes to an ordinary google web search Y- chromosomal adam wins
 * Y chromosomal Adam 322000 hits
 * Y chromosome Adam 16300 hits.
 * But when we use google scholar, the result is different
 * Y chromosomal Adam google scholar search has 62 hits
 * Y chromosome Adam google scholar search has 97 hits
 * Google books is also similar
 * Y chromosomal Adam google book search has 158 hits
 * Y chromosome Adam google book search has 232 hits
 * In summary, with a general web search Y-chromosomal Adam seems to be the more common name. I suspect this is because of references to the wikipedia article. But in scientific and educational literature, "Y chromosome Adam" seems to be preferred. Wapondaponda (talk) 01:05, 25 July 2011 (UTC)

 * Week Support as per Y chromosome and X chromosome conventional styles that were recently changed  without complaints  - Although  this may  require a much  broader talk. This "style" of having  Y-DNA is the current format used for most titles in this family of articles. As seen with Human Y-chromosome DNA haplogroup and   Y-chromosome haplogroups by populations sub pages.Moxy (talk) 02:44, 25 July 2011 (UTC)

So what do we call mtEve? -- cheers, Michael C. Price talk 03:39, 25 July 2011 (UTC)
 * Michael C. Price could you stop elaborating so much in your edits they are so lengthy that they are  tedious to read :-(.  Again as mentioned above those within the  Y-DNA family are of this style.Moxy (talk)
 * Consistency is relevant. Mitochondrion Eve it is? -- cheers, Michael C. Price talk 04:09, 25 July 2011 (UTC)
 * It is a case of an irregular convention. Moxy has made a good point, we have Human Y-chromosome DNA haplogroup but we have Human mitochondrial DNA haplogroup. So the convention seems to be mitochondrial rather than mitochondrion and y chromosome rather than y-chromosomal. Wapondaponda (talk) 11:07, 25 July 2011 (UTC)

Does this mean all men before Adam have no descendants?
Same with eve, no women before her have any descendants? — Preceding unsigned comment added by 88.104.98.252 (talk) 18:17, 9 August 2011 (UTC)
 * How could there be any people if that was the case! -- cheers, Michael C. Price talk 18:38, 9 August 2011 (UTC)
 * THERE WERE HUMANS BEFORE Y-Chromosomal ADAM, since all males are descended from him, does it mean humans other than Y-Chromsonal Adam have descendants? — Preceding unsigned comment added by 88.104.97.12 (talk) 13:54, 26 August 2011 (UTC)
 * Actually, all humans now living, but not by the paternal line. -- cheers, Michael C. Price talk 16:50, 26 August 2011 (UTC)
 * To rephrase 88.104.98.252's question, since by definition, all males now living are descended from Y-Chromosomal ADAM by the paternal line, but there were other humans not descended from Adam (descended from Adam's uncles for example), does this mean that some humans now living could be descended from Adam's uncles by a different paternal line and not be descended from Adam by his paternal line? The answer is no, by definition, but there could have been many males descended by a different paternal line from Adam's uncles and who all died years ago and hence are excluded from "all males now living" in the definition of Y-Chromosomal ADAM.  Greensburger (talk) 18:38, 26 August 2011 (UTC)

 * No it means that all males who were neither ancestral to y-Adam nor descendant from him have a descendant sub-trees whose surviving lineage at the leaf nodes are solely females. Qed (talk) 23:52, 6 March 2013 (UTC)

Timing of Out-of-Africa migration relative to Y-chromosome Adam
The page says that the date of 59,000 years ago for Y-chromosome Adam, proposed by initial studies such as Thomson et al. 2000, "meant that Y-chromosome Adam lived at a time very close to, and possibly after, the out of Africa migration". In good faith I removed the words "and possibly after", with the explanation "Y-chromosome Adam cannot have lived after the out-of-Africa migration". Another user has restored the words, also in good faith, with the explanation "No, your logic is false - it is possible".

I am not an expert, but I thought I understood this. On the Recent African Origin model (which the sentence in question presupposes by using the phrase "the out of Africa migration") members of one branch of Homo sapiens left Africa by between 125,000 and 60,000 years ago, in what may be called the earliest successful "out of Africa" migration (the earliest migrants with living descendants), and over time these humans replaced earlier human populations such as Neanderthals and Homo erectus. Surely then Y-chromosomal Adam, who is defined as the most recent common patrilineal ancestor, must in all but the most absurd scenarios have preceded the migration? When I say "the most absurd scenarios" I am thinking for example about a scenario in which the earliest successful out-of-Africa migration came to the point of extinction, there being only females (and possibly infertile males) left, and was saved by males from a subsequent wave of migration finding them and breeding with them; does anyone seriously put forward such a scenario?

On the major competing hypothesis, the multiregional origin of modern humans, which envisions a wave of Homo sapiens migrating from Africa and interbreeding with local Homo erectus populations in multiple regions of the globe, the date of Y-chromosomal Adam can only be pushed further back, not pulled forward.

Elsewhere on the same page there is the assertion: "The defining mutations separating CT (all haplogroups excepting A and B) are M168 and M294. These mutations predate the 'Out of Africa' migration." No "probably" there. And that assertion entails that Y-chromosomal Adam preceded the migration.

Can anyone who knows about these things confirm what I have said, or explain why I am wrong please? Prim Ethics (talk) 01:37, 22 November 2011 (UTC)
 * The scenarios don't have to be that absurd. Suppose a favourable mutation occurs on the Y-chromosome in a male that confers an advantage to all his male descendants.  Even a very slight advantage will cause the Y chromosome to dominate within a surprisingly short time, without having to suppose a sudden decimation of other males.  It doesn't matter whether this male (Y-chromosomal Adam) lived before or after a particular out-of-Africa migration, inside or outside Africa, since there were later back-into-Africa waves.  -- cheers, Michael C. Price talk 06:53, 22 November 2011 (UTC)
 * The confusion over dates arises because the time frames suggested for when Y-Adam lived overlap with the "out of Africa" migration. Typically the Out of Africa migration is dated to between 50,000 -80,000 years ago. If Y-Adam lived 59,000 years ago, as had been suggested by, then it could in theory mean he lived after the out of africa migration. But the final sentence in the section Y-chromosomal_Adam states "According to Cruciani et al., the much older date is easier to reconcile with models of human origins". Basically recent dates have been published, but as Prim Ethics has mentioned, they don't chime well with models of human origins. Wapondaponda (talk) 09:03, 22 November 2011 (UTC)
 * Thanks, Michael. I am comfortable with your revert now. Prim Ethics (talk) 12:52, 22 November 2011 (UTC)
 * Thanks. However, I must grant, that whilst it is possible that Y-Adam lived outside Africa, it does seem most unlikely, from the haplogroup data.-- cheers, Michael C. Price talk 17:59, 22 November 2011 (UTC)

Adam (and the MRCA) is not 'theoretical'
The article initially asserts that Adam is the 'theoretical' MRCA. Although (according to the article) the existence of Y-chromosomal Adam follows from the theory of molecular evolution, the actual wording of the initial sentence gives the reader the impression that Y-chromosomal Adam exists only in theory, but not (necessarily) in practice. Although few specifics can be given about Adam (and MRCAs in general), those specifics apply to a human that actually walked this planet - unless one rejects the entire scientific theory of (molecular) evolution. As such I am removing the word. Otherwise _anything_ that established scientific theory predicts as existing can be labelled 'theoretical', like a 'theoretical' heavier-than-air aircraft. Please revert the edit only after justifying it here. Thanks. Lklundin (talk) 22:17, 23 January 2012 (UTC)

Semitism
Why is he called Adam? Was he Jewish or Muslim? This choice of naming is discriminatory.--144.122.104.211 (talk) 13:51, 29 January 2013 (UTC)
 * hmm perhaps Eskimo and should obviously be named Charley (as in Brown).
 * Take your discrimination blather elsewhere, we just report what the reliable sources use. Vsmith (talk) 14:19, 29 January 2013 (UTC)
 * WP:NPA; WP:AGF--144.122.104.211 (talk) 22:40, 2 May 2013 (UTC)
 * Well if you are going to assume someone is in violation of WP:AGF you should start with yourself. He is called Adam because that's what scientific sources call him. Obviously the name "Adam" is not some capricious choice made by Wikipedians. If you want to make a contribution to Wikipedia why don't you try researching this for yourself, and fill in the answer yourself? Qed (talk) 00:21, 9 May 2013 (UTC)
 * Do you mean that if someone doesn't contribute to an article he or she cannot criticise the content? or Do you mean that if someone doesn't contribute to an article he or she cannot call for WP:AGF? Where do all these come from?--144.122.104.211 (talk) 22:13, 29 May 2013 (UTC)
 * He was neither Jewish nor Muslim; neither the Jewish race nor the Muslim religion existed at the time of Adam (either Biblical or symbolic). This is rather clear to me in the article's lead section. All choices are discriminatory in some sense; however Wikipedia uses standard terminology that would appear in any encyclopedic coverage. As Vsmith pointed out the scientific community generally uses 'Adam' and 'Eve' to indicate these chromosomal 'people'. I believe we are willing to consider alternative terminology which is regularly used in the scientific community or journalism. SBaker43 (talk) 01:55, 30 May 2013 (UTC)

Article needs to be rewritten: Adam is now 340,000 years ago
New unrelated Y Chromosome discovered:. Thue (talk) 19:04, 6 March 2013 (UTC)

 * I don't think *rewritten* is the right prescription. First of all, we have to wait for scientific sources to flush this out properly so we know exactly what to write.  One paper is great, but other scientists may have something to add to this.  For example, my initial intuition is to say that Homo sapiens have a >99.99% y-Chromosome Adam that is 140,000 years old, and a very small subset of archaic y-Chromosome preservation from something like Homo rhodesiensis in a very small subset of individuals.  It's almost as if we have partial brother species living among us.  But the simple fact is that with the Neanderthal and Denisovan infusion discoveries in the last 3 years, we should not be at all surprised by this.  This strikes me as requiring a better designation, like preponderant y-Chromosome Adam (who corresponds to the data we have excluding this anomalous/rare case), versus strict y-Chromosome Adam (which includes this case).  The reason to make this distinction, of course, is because many thousands of genomes were used to converge towards the preponderant result.  So this one very rare y-Chromosome instance is asking us to add 200,000 years of ancestry to the story just because of him alone, without any of the individuals from those 200,000 years having a say.  And all that just to tell us that there was a co-existing archaic that was not "genetically drifted out" and interbred with a very small sub-group of surviving Africans.  Analytically it just seems like an almost useless data point; at least without a closer inspection of the other 45 chromosomes.  Qed (talk) 00:16, 7 March 2013 (UTC)
 * Although extremely rare, It's not a single case any more, a simular Y-chromosome was also found in the samples of 11 (unrelated) idividuals among the Mbo people in western Cameroon.  Arber52 (talk) 01:50, 7 March 2013 (UTC)
 * I agree with all that. But doesn't incorporating all the true things you said amount to rewriting the article? Thue (talk) 08:59, 7 March 2013 (UTC)

 * Qed, I don't think you understand. You want to see this as some kind of anomaly, but your "intuition" which speaks to you is not relevant to what a Wikipedia article should objectively report. To say that "It's almost as if we have partial brother species living among us" reveals your misunderstanding. The men bearing the A00 Y-chromosome are every bit as modern humans as you or I. The humans who contributed the A00 Y chromosome lived many thousands of years ago.  The most recent date for any admixture that any evidence suggests would be 13,000 years ago, the estimated age of the somewhat archaic remains found at Iwo Eleru.  In the time between then and now, any archaic DNA will have been very thoroughly mixed throughout the vast West-Central African population.
 * Agreed. The way I read the argument concerning the 'partial brother species living among us' and the idea to disregard that person's Y-DNA in estimating the time to Y-MRCA, implies that he would not actually consider that person to be human. I find the reasoning absurd. Also, the fact that the quoted article with the revised TMRCA has been peer reviewed implies that Wikipedia can consider it a reliable source (subject to future revision, like any other science). Lklundin (talk) 09:31, 9 March 2013 (UTC)
 * You make it sound like I am just imposing my personal opinions, and they happened to be racist or speciesist or something. Look, when we found out that non-Africans were all 1-4% Neanderthal, and that Oceanic people were 5% Denisovan, the scientific community did not decide to designate three kinds of Homo sapiens (such as Homo sapien africanus, Homo sapien oceanicus, and Homo sapien eurasianicus) even though one could argue that those distinctions are more useful from a genetic point of view.  Instead we have retained the default designations, and describe the reality by differences to the original ideas.  Ultimately, it is a scientific term. The y-Chromosome Adam designation without this 300kya influx has analytic usefulness, as we understand what too look for in terms the y-Chromosome of Neanderthal, the exodus from Africa, etc.  With the 300kya minority influx we are stuck in this situation where we are making exceptions and using contorted designations and language just to describe what we are talking about.  The fact that the Papua New Guineans are 5% archaic Denisova is interesting, but doesn't change the definition of homo sapien, and there's no implication that they are less than homo sapiens because of our lack of active inclusion of them.  Same with these new Cameroon hybrids. Qed (talk) 00:02, 13 April 2013 (UTC)
 * Furthermore, there are not only 12 members of the A00 clade. First, consider, as Dr. Hammer was quoted as saying in an article, that he estimates that some 1000 descendants of the enslaved Albert Perry (b abt 1827 ) are likely to be living in the United States now. In Cameroon, closely matching samples from the SMGF database show at least ten individuals from Fontem, home of the Bangwa people who are neighbors of the Mbo.  Certainly not every member of the Mbo or Bangwa were tested, so these are only a representative sample. As these lineages have been in existence for such a long time in their homeland, it seems highly probable that there would be a greater number living there in Africa, than in the U.S. Iris-J2 (talk) 18:46, 8 March 2013 (UTC)

 * There is also a discussion at Talk:Recent African origin of modern humans which was advertised on several boards on March 5. Can you all please talk about this in one place? HelenOnline (talk) 09:27, 7 March 2013 (UTC)
 * I read the scientific paper and I think the current status of the article is currently about right. It achieves three things:
 * Shows the recent history of research, demonstrating how Adam can change when new lineages are discovered, and that the dating techniques are quite inexact.
 * Includes the most recent scientific theory, without dismissing the old ones before consensus in the scientific community is formed.
 * Effectively discusses the two individuals (strict and preponderant Adam) that Qed defines above.
 * My reckoning is that because to date African genetics have been far less extensively studied than that of Europeans there could be significant developments in this field still to come. --LukeSurlt c 22:39, 7 March 2013 (UTC)
 * That makes sense, especially considering that the paper with the new estimate of the time to Y-MRCA mentions Y-DNA from an African American. Lklundin (talk) 09:35, 9 March 2013 (UTC)

What about Adam's brother?
"Y-chromosomal Adam is named after the biblical Adam. He co-existed with other human males and was not the only human male alive during his time.[4] However none of his male contemporaries produced a direct unbroken male line to a male living today."

Suppose Adam had a brother. Adam's brother has the same Y chromosome as Adam. How can you then claim to know that none of Adam's male contemporaries produced a direct unbroken male line to a male living today ? How can a descendant of Adam's brother be distinguished from a descendant of Adam ? Eregli bob (talk) 12:08, 8 March 2013 (UTC)

 * The formulation is prob nonsense. "Y-chromosomal Adam" is a symbol for a small subpopulation of males. Brothers, uncles, dads and sons. That subpopulation was part of a larger population of males whose Y-chromosomes didn't propagate (but other genes most probably did). Rursus dixit. ( m bork3 !) 12:32, 8 March 2013 (UTC)

 * For the rest I propose refraining from using the word "biblical". For us biblical-critical Christians it is a label of idiocy (by all literalist calling themselves "biblical"), that mayhap give the text a stupid tone. Rursus dixit. ( m bork3 !) 12:39, 8 March 2013 (UTC)

 * Thats not my word "biblical". The first three sentences are a direct quote of the second section of the article as it stands now.Eregli bob (talk) 14:33, 8 March 2013 (UTC)
 * "Y-chromosomal Adam" is a definition. By definition, a definition cannot (and thus does not have to) be proved. It is true because it is defined to be true. The article on MRCA explains why Y-chromosomal Adam exists, which is a somewhat different, but related matter. Lklundin (talk) 19:33, 8 March 2013 (UTC)

 * "He" is a statistical construct rather than a real person, but no, his father and brothers would not have had all the markers he had. The key to defining Y-chromosomal Adam lies with some mutation that has unique to "him". Guettarda (talk) 20:06, 8 March 2013 (UTC)

 * I see. Thanks. Rursus dixit. ( m bork3 !) 07:44, 9 March 2013 (UTC)
 * No, that is not true. Y-chromosomal Adam is the Y-chromosomal MRCA of all men. The 'MR' means most recent, which implies that he had two sons who both have living, patrilineal descendants. Y-chromosomal Adam may have inherited an exact copy (i.e. with no mutations) of his fathers Y-chromosome. His father would however not be Y-chromosomal Adam, because he would not the the most recent patrilineal ancestor of all men. Y-chromosomal Adam is therefore not a statistical construct, but a man who walked this Earth. The fact that the title of Y-chromosomal Adam changes from one man to one of his descendants at distinct (but typically unknown) times, is something else. Lklundin (talk) 09:00, 9 March 2013 (UTC)
 * Should the term not refer to the earliest patrilineal ancestor of all men?
 * I have just read the MRCA article which makes clear what the term means. Ignore that, although I am not sure that 'Adam' is the right name. Martin Hogbin (talk) 10:27, 9 March 2013 (UTC)
 * Go read up in "speciation". Think about where one draws the line to determine some individual is a member of a new species, while his father is not.  That would be your earliest ancestor, if you can determine where the line occurs. SkoreKeep (talk) 06:09, 13 March 2013 (UTC)
 * This discussion is also relevant to my section below. Y-cA is indeed believed to be a real individual but we are not sure exactly who and probably will never be able to determine many of his important unique features. Martin Hogbin (talk) 10:08, 9 March 2013 (UTC)

Proposed/postulated/notional/hypothesised...
The article gives the impression that Y-chromosomal Adam was an identified individual rather than an individual whose existence has been scientifically deduced. Should we not say a hypothesised/notional man?

This comment has nothing to do with the evidence for or against Y-c A, just the way it is explained in this article. particularly the lead. Martin Hogbin (talk) 17:26, 8 March 2013 (UTC)

 * I don't think so. The article states very clearly how Y-chromosomal Adam is defined, and goes on to provide estimates for when this man walked the Earth. It seems completely clear to me.
 * One could elaborate: 'Y-chromosomal Adam is the name given to an actual man, who is the most recent common ancestor (MRCA) from whom all living people are descended patrilineally (tracing back only along the paternal (male) lines of their family tree.
 * I think something like that is overly verbose and unneeded. There is a link to MRCA, which is the concept upon which this article builds. The reader can follow the MRCA link to understand that it refers to an actual person, that have walked this Earth. Lklundin (talk) 17:50, 8 March 2013 (UTC)
 * Yes, I understand that but my point relates to the opposite misconception, that Y-cA refers to a specific archaeological find. Martin Hogbin (talk) 18:36, 8 March 2013 (UTC)
 * How about 'unidentified'. Martin Hogbin (talk) 10:29, 9 March 2013 (UTC)
 * A wikipedian inserted the 'defined as', so the initial sentence reads: "the Y-chromosomal Adam (Y-MRCA) is defined as the most recent common ancestor (MRCA) from whom all living people are descended patrilineally". I think it is quite clear and that the suggested modifiers ('notional' included) confuse the matter by expressing doubt that this man existed. The existance of Y-MRCA rests on the concept of MRCA, so the introduction of a word such as notional here would require the same modification in other MRCA articles. Lklundin (talk) 12:05, 10 March 2013 (UTC)
 * Thanks for responding, my edit was a bit bold (please feel free to revert) but I wanted to start a discussion. I do agree that 'defined as' does actually make the position clear although it does not sit well, in my opinion, with giving the defined individual a name.
 * The existence of Y-chromosomal Adam follows from the existence of a Most Recent Common Ancestor (MRCA), which is a) accepted by science as existing and b) an essential concept in several articles. So anyone wishing to introduce a term such as those suggested, will have to A) explain why results of established science are to be ignored and B) make their case succesfully for 'all' wikipedia articles that rely on the concept of an MRCA. I am remving 'notional' until then. Lklundin (talk) 19:36, 12 March 2013 (UTC)

 * To explain my perspective, I am a physicist and a newcomer to this page. Pretty well everything I know about this subject I know from reading this article.  That is a good and a bad thing.  I am in no position to challenge the biology, and indeed I have no desire to do so, but I can view the article more as a general reader than the regular editors can. (If anyone here would like to give their initial impressions of the Monty Hall problem they would be most welcome.)

 * I see two issues. Firstly, from what I can understand, the individual to whom the definition applies could change as we discover new information.  This fact, in my opinion, justifies the term 'notional'.

 * Secondly, even it it somehow becomes known that the individual fitting the definition cannot change, we are very unlikely to ever be able to identify them in any normal sense of the word. This would, to me, justify the use of 'unidentified'.

 * My comments are more about making things clear to our readers and avoiding possible misconceptions rather than stating facts. Martin Hogbin (talk) 12:54, 10 March 2013 (UTC)

 * The intro, as formerly written, did indeed make it seem that this person was objectively known, and not hypothesized or inferred from the data available today. I'm all for noting that this is not a definitive identification, and doing so right at the outset; "hypothesized", "notional", or "inferred" could be used. --Piledhigheranddeeper (talk) 17:19, 12 March 2013 (UTC)

 * I hope that "the most recent common ancestor from whom all living people descend patrilineally", including myself, was a real person and not a notional one. Just because we don't know his name (if he even had one) does not mean he was notional i.e. imaginary. HelenOnline (talk) 20:53, 12 March 2013 (UTC)

 * Actually, it's not universally accepted that there was one single person from whom all humans are descended. Alternative hypotheses include that there was a small group of contemporaneous ancestors, none of whom is ancestor to all of us.  (See, e.g., this: "all modern humans descended from the same small group of people".) --Piledhigheranddeeper (talk) 12:00, 13 March 2013 (UTC)
 * The cited source cannot be used in this context: The cited source clearly talks about a different topic, namely the migration of humans out of Africa, and it states "The research confirms the “Out Of Africa” hypothesis that all modern humans stem from a single group of Homo sapiens". So clearly, no person in this group is Y-chromosomal Adam. Please do not modify this article by cherry-picking such quotes. Lklundin (talk) 12:19, 13 March 2013 (UTC)

 * Clearly someone is challenging the science here. Subtle (or not) changes in wording are not the way to go about it. HelenOnline (talk) 12:23, 13 March 2013 (UTC)

 * What word would you suggest? Martin Hogbin (talk) 23:12, 12 March 2013 (UTC)
 * None. I don't think it's necessary to qualify the name further, most recent common ancestor goes into more detail for those who need it. HelenOnline (talk) 08:26, 13 March 2013 (UTC)
 * The first sentence also starts with "In human genetics...", so I don't see how the article does not give the impression that Y-chromosomal Adam was scientifically deduced. If the reader doesn't understand the subject, they need to click on the wikilinks to find out more. HelenOnline (talk) 21:32, 12 March 2013 (UTC)
 * Of course, it is our readers' fault that they do not understand the subject. Shame on them. Martin Hogbin (talk) 23:12, 12 March 2013 (UTC)
 * I am not shaming anyone. I click on wikilinks all the time. I don't expect editors to duplicate information on every page. That is how Wikipedia works. HelenOnline (talk) 08:26, 13 March 2013 (UTC)
 * I am assuming good faith here. The alternative is that you are trying to assert your personal point of view about the science in this article which is not acceptable. HelenOnline (talk) 08:26, 13 March 2013 (UTC)
 * HelenOnline, please read what I have written above, I am in no position to challenge the biology, and indeed I have no desire to do so. What I am trying to do is make the situation easier for our readers to understand.  The problem is that the regular biologists here understand the situation very well and therefore find it hard to put themselves in the position of a general reader. Wikilinks are excellent and of course we all use them but a little clarification in the article itself will go a long way.  Martin Hogbin (talk) 09:31, 13 March 2013 (UTC)
 * I have but the most superficial knowledge of biology and yet I consider the article on Y-chromosomal Adam to be abundantly clear. Regarding this article, I think you need not to worry about your fellow readers. Lklundin (talk) 07:08, 14 March 2013 (UTC)
 * It is our job to worry about our fellow readers; we are writing an encyclopedia. Just because you got it straight away does not mean that everyone else will.  I do not understand your objection to trying to make what you and I and many others understand clearer to everyone.  I am not demanding any specific wording, just suggesting that we work together to avoid possible misunderstandings.

 * Part of the problem is the, somewhat jocular, name given to what is a rather technical specification of an individual. Some people might see our subject like Arlington_Springs_Man or Buhl Woman. Martin Hogbin (talk) 14:39, 14 March 2013 (UTC)

 * The same logic can be applied to the opposite effect: Why should we change something that is perfectly clear to us? If it turns out that someone actually has a problem with this article, why not let them state the problem and hear their suggestion? If you feel compelled to 'worry about our fellow readers; we are writing an encyclopedia', then there are plenty of agreed-upon things to fix in a number of articles. Lklundin (talk) 09:18, 15 March 2013 (UTC)

 * I have chosen to help with this article and I want to make it as clear as I can to the widest range of readers. If we can anticipate a problem with understanding then we should fix it, provided we can do so without compromising the scientific integrity and quality of the article.

 * As I have said before, I am not demanding any specific wording, just that we should make clear to our readers that an individual who has been given a name has not be identified in the normal sense of that word. What is your objection to this? Martin Hogbin (talk) 12:47, 15 March 2013 (UTC)

BRD
People, I am trying to follow the WP:BRD principle here. I have made some bold changes and had them reverted, with some rather terse edit summaries. I am trying to initiate a sensible and civil discussion on how we can improve the wording of this article to make the situation clearer to the general reader.

Can someone tell me what is wrong with saying 'unidentified'. Martin Hogbin (talk) 09:31, 13 March 2013 (UTC)

 * My problem is such terms are redundant (see most recent common ancestor) and possibly misleading or confusing. Y-chromosomal Adam is not notional (imaginary) or unidentified, his Y-DNA sequence has been identified via the Y-chromosome phylogenetic tree established by scientific consensus and he has been given a name. Quoting from most recent common ancestor, "Mitochondrial Eve and Y-chromosomal Adam have been established by researchers using genealogical DNA tests." Identified doesn't only mean a physically identified body or person. HelenOnline (talk) 10:54, 13 March 2013 (UTC)
 * Helen, please stop bandying terms like scientific consensus around. If you think that I am trying to go against any scientific consensus then please tell me which. Martin Hogbin (talk) 00:35, 14 March 2013 (UTC)
 * All MRCA-related articles rightly stay away from redundancies such as 'unidentified'. Lklundin (talk) 07:03, 14 March 2013 (UTC)

 * I agree. Lklundin (talk) 12:19, 13 March 2013 (UTC)

 * I will also point out that the mentioned, bold changes were made without regard to prior postings on this topic here on the Talk Page (Talk:Y-chromosomal_Adam and Talk:Y-chromosomal_Adam). I think the correct approach would have been to first consider the arguments there and then if new arguments are found, then reopen the discussion. Lklundin (talk) 13:51, 13 March 2013 (UTC)

 * Let us assume that the definition of YcA given permanently describes one fixed unique individual (which from the article itself seems actually not to be the case). Even then the term 'unidentified' is perfectly justified. Yes, we know that this person existed but using the normal meaning of the word we do not know their identity and are very unlikely in the foreseeable future to do so.  We cannot even be sure that he was a human.

 * As an example of what I mean, see Jack the ripper. The name undoubtedly refers to a single individual, whose identity cannot change, yet he is 'unidentified'.  This is normal English usage that cannot be changed by the biological context.  Martin Hogbin (talk) 00:35, 14 March 2013 (UTC)

 * That he was not human? Humans (Homo) are 2.5 million years old. Adam has hardly half a million.--Maulucioni (talk) 04:30, 14 March 2013 (UTC)
 * Not by the definition given in Human. The point is that, apart from his y-chromosome, we know very little indeed about this individual, certainly nothing that in normal parlance could be called an identity.

 * The assumption is useless since it will never be true. Still, you go on to say 'we know that this person existed but using the normal meaning of the word'. Having every living person on the planet as your descendant must be about the most tangible example of existence that a human can have. Can we please put this tedious discussion to rest? Lklundin (talk) 07:03, 14 March 2013 (UTC)

 * It is clear from your misquotation of me above that you have not yet understood the point I am making. I said 'we know that this person existed but using the normal meaning of the word we do not know their identity ', meaning, using the normal meaning of he word 'identity' we do not know their identity.  There is no argument about the biology just about the correct use of the English language. As you have not yet understood what I am talking about, the answer to your question is, 'No we cannot put this discussion to rest'

.
 * I know he existed but he has not been identified in the normal English language meaning of the word. Specifying a unique individual does not identify them.  Let me give you another example.  Whatever definition we use there must a been a first Homo sapiens.  Given a precise enough definition of Homo sapiens, the first Homo sapiens specifies a unique individual.  Are you saying that I have now identified that person? Martin Hogbin (talk) 09:01, 14 March 2013 (UTC)
 * I just happened onto this discussion and was immediately struck by the possibility that you might be interested to know that articles of this type are needed in the Simple English Wikipedia. It takes significant talent and ability and patience to paraphrase concepts in a readable simple form suitable for people with reading disabilities and from some of the sentiments expressed above I thought it might appeal to you. Trilobitealive (talk) 23:52, 14 March 2013 (UTC)
 * Thank you for your suggestion; it is one that I might take up. However, there is still work to do here, and on this article. Do you see any reason why we should not make it clearer that the subject of this article has not been identified in the way that one would normally expect a named individual to be. Martin Hogbin (talk) 09:53, 15 March 2013 (UTC)
 * Martin Hogbin, earlier in the discussion you chose to assert your background as a physicist. Since any physicist surely can accept the existence of a number of non-tangible or otherwise elusive objects, I am surprised by your insistence that 'existence' must be qualified with either 'identified' or in this case 'unidentified'. I am in other words questioning your motives for wishing to modify this article. Lklundin (talk) 09:11, 15 March 2013 (UTC)
 * Lklundin, I have no idea why you need to be so defensive when all I am trying to do is help the article reach a wider audience. I cannot imagine what ulterior motives you think I have for the change I want to make. Perhaps you could tell me what you think they are.

 * I want to distinguish between 'identified' and 'unidentified' because there is a distinction, and one that not everybody might perceive.  Because the subject of the article has been given a name, it can easily appear that there is an identified (in the normal meaning of the word) individual involved, as in Arlington_Springs_Man, Buhl Woman.  Had the article just been called 'Most recent common patrilineal ancestor' this is issue would probably not have arisen.

 * What reason do you give for not making this point clear to our readers? Martin Hogbin (talk) 09:53, 15 March 2013 (UTC)
 * To conclude: "One wikipedian thinks that someone may find the article unclear and argues for a change, while others argue against this change". That seems to me to be a really weak case for change. I took the time to check the Contributions of Martin Hogbin. It turns out that you spend a significant amount of time on Wikipedia, and almost all of that time is spent in drawn out Talk Page discussions. Based on these combined observations I will conclude my part of the discusion as follows: 1) Martin Hogbin, if you feel like it, go ahead and unilaterally make the changes you wish for. I will not revert it. I suspect that others may, but time may tell. 2) If you are not just intent on starting and 'winning' drawn out discussions, but instead truly interested in improving Wikipedia, I suggest you shift the majority of your contributions away from the Talk pages and on to the actual articles. As already suggested by someone else, you can for example knock yourself out on an article on Y-chromosomal Adam in Simple English where you can detail all your perceived need for details regarding the lack of that man's identify. Good Luck. Lklundin (talk) 20:00, 15 March 2013 (UTC)

Would adding a sentence something like this (without the bold font) in the lead solve your problem?

"In human genetics, Y-chromosomal Adam (Y-MRCA) is the name given to the most recent common ancestor (MRCA) from whom all currently living people are descended patrilineally (...). He is the bearer of the Y-chromosome at the root of the Y-chromosome phylogenetic tree, which has been established by researchers using genealogical DNA tests of currently living people and is subject to review as new information becomes available. A paper published in March 2013 determined ...". HelenOnline (talk) 16:04, 15 March 2013 (UTC)

 * That looks promising to me. Could we have (addition in bold), ...of currently living people and his identity is subject to review...'?  Martin Hogbin (talk) 17:40, 15 March 2013 (UTC)
 * It is the whole tree, including Y-MRCA at the root, that is subject to review. That is the point I was trying to make and I don't think it is helpful or necessary to exclude the rest of the tree in that respect. I personally don't support the use of the word identity here as it is a complex and potentially loaded concept. HelenOnline (talk) 18:50, 15 March 2013 (UTC)
 * How does using the word 'identity' exclude anything?
 * In what way is it a complex and loaded concept?
 * These are genuine questions. Martin Hogbin (talk) 20:11, 15 March 2013 (UTC)
 * The two words his identity exclude the rest of the tree. You would be introducing a term with many possible meanings (so complex), and you would have to define exactly what you mean by it so that we don't have more prolonged discussions like this one. We have already demonstrated that we cannot all agree on the meaning of the words identified and unidentified so why introduce a related word we are unlikely to agree on the meaning of (so loaded)? HelenOnline (talk) 20:26, 15 March 2013 (UTC)
 * I see, I misunderstood your proposed wording, it is the tree that is subject to review not the individual.

 * I think the word 'identified' has a generally understood meaning that is not the same as 'uniquely specified' or 'uniquely determined'. There was a first Homo sapiens and a first person to say the word that but would you say that I have identified these individuals?

 * I am not insisting on any particular word or wording and I think we are making progress. Could you suggest something along the lines given above that makes clearer the distinction that I am making. Martin Hogbin (talk) 21:15, 15 March 2013 (UTC)
 * For what it is worth, I also think the suggested 'identity is subject to review' would be a mistake. We will never know the 'identity' of this man, and any talk of identity is just confusing. Lklundin (talk) 20:00, 15 March 2013 (UTC)
 * I that not what I have been saying all along, "We will never know the 'identity' of this man"? so what then is the objection to calling him 'unidentified' ? Martin Hogbin (talk) 20:11, 15 March 2013 (UTC)

Nonsense in the Variable Adam section
"Alternatively, the lineages of all those sons could die out, this would however imply the extinction of (the male half of) humanity."

Unless humans somehow developed asexual reproduction in a single generation the parenthetical is both redundant and stupid. — Preceding unsigned comment added by 69.255.170.233 (talk) 06:06, 10 March 2013 (UTC)

 * Perhaps not, as it's arguably just intelligent but confusing. Since it hasn't yet happened, the extinction of all human males can only happen at some time in the future, and at such a time it is perfectly possible that science would have reached a stage where females could reproduce asexually (our cloning technology may well mean that science is already almost there), so that such an event would not automatically imply the extinction of humankind. This was almost advocated by 'feminist' extremist Valerie Solanas in her SCUM (Society for Cutting Up Men) Manifesto, which got much publicity after she shot the artist Andy Warhol, a shooting which I mention to make clear she was not self-evidently just some kind of harmless dark humourist, although I don't entirely rule out the possibility that she was a humourist modelling herself on predecessors like Jonathon Swift and his 'A Modest Proposal', and that she just also happened to be prone to violence (I might add that I don't think the usual use of the label 'feminist' in her case is particularly fair on other feminists). However, strictly speaking, she thought it would be necessary to allow a few male scientists to survive to carry on inventing domestic labour-saving devices for the benefit of women, so that in this instance there would still have been a Y-chromosomal Adam - but presumably her modern successors, if any, would argue that female scientists were well able to invent domestic labour-saving devices without male help, so there would be no need to preserve any males.

 * But what is much less clear is how precisely we should change the article to clear up such confusion. But I think I'm going to change it to "this would however imply the extinction of humankind (unless Science by then allowed the female half of humankind to continue through asexual reproduction).", and then I'll just wait and see what, if anything, happens.Tlhslobus (talk) 08:01, 10 March 2013 (UTC)

 * I believe then preceeding sentence "If the lineages of all but one of those sons die out, then ..." may raise the question "What if all the lineages die out" ? To cover that (hypothetical) case I wrote the sentence with the contested parentheses. The sentence is in no way essential to understanding the topic and if it confuses more than it expains, then it should be rewritten or removed. The suggestion for improvement certainly makes sense, although I would prefer something shorter given that it is covering a (hopefully highly) hypothetical case. Lklundin (talk) 08:47, 10 March 2013 (UTC)

 * Done, but I've also changed 'die out' to 'die out (or be killed)' as otherwise it requires a lot more imagination for a reader to work out how all males could simply die out. Presumably one could imagine some kind of highly contagious disease that was 100% fatal to men but not to women; and so on. But I'm not sure such speculations should be mentioned here, as presumably the most we need to do is briefly explain in an understandable manner how humankind might not always have a Y-chromosomal Adam in the future, which I think I'll now try and briefly spell out explicitly. Tlhslobus (talk) 08:39, 10 March 2013 (UTC)

 * OK. As for the 'die out (or be killed)' I speculate that the title of 'Y-chromosomal Adam' has changed hands a number of times, exactly because one tribe used its superiour technology to exterminate another tribe thus freeing up resources for themselves. Spelling such details out also in this case is fine by me. Lklundin (talk) 08:50, 10 March 2013 (UTC)

 * Thanks. I think it was an excellent idea of yours to get the ball rolling. Also, if you can think of ways to shorten it without making it less informative or less understandable, please feel free to do so. My current feeling is 'it ain't broke, so I ain't gonna try to fix it' - but don't let my feeling stop you if you think you can improve it. Tlhslobus (talk) 09:14, 10 March 2013 (UTC)

 * Having said it ain't broke, I then proceeded to fix it anyway, by spelling out explicitly that it was 'an all-female' humankind that could them continue with no Y-chromosomal Adam, as I guess the idea is sufficiently unfamiliar to readers that it probably needs such explicit explanation. Tlhslobus (talk) 09:29, 10 March 2013 (UTC)

 * Ouch. I've just had serious second thoughts, and I now think the entire sentence should be deleted as Original Research under WP:NOR. Because it isn't obvious that there is no Y-chromosomal Adam if all males are extinct and females carry on a female-only race (even assuming they don't use science to resurrect males, as I expect they would try to do). It is at least equally arguable, and probably more so, that there is still a Y-chromosomal Adam, the guy who is the most recent common male ancestor of all surviving women. So unless and until a Reliable Source is found to say what happens in this case, I now think the entire sentence should be deleted, because it can't legitimately tell us anything about the Y-chromosomal Adam. So I'm deleting it as OR. If anybody else wants to keep it they can easily revert me. I won't bother to object, but then they'll have to defend it against anybody else objecting that it's OR. Tlhslobus (talk) 10:00, 10 March 2013 (UTC)
 * Fair enough. Lklundin (talk) 11:25, 10 March 2013 (UTC)

 * Seriously? — Preceding unsigned comment added by 69.255.170.233 (talk) 03:57, 21 March 2013 (UTC)

"Initial sequencing?"
The term "initial sequencing" is apparently used in the article to refer to some early study that (apparently) was the first to identify the haplotyopes using the letters A through T and which (apparently) found that "Adam" is 60,000 years old. I edited the article to identify "initial sequencing" with (Karafet et al., 2008), based on the figure. However, I don't think this is correct. Can an expert please provide a date and a reference for "initial sequencing?" It's really quite important from a history of science perspective. As teh article ages, we tend to lose sight of history as more recent studies are reported. -Arch dude (talk) 16:21, 10 March 2013 (UTC)

Mendez et al. 2013
The Mendez et al. article states
 * Genotyping of a DNA sample that was submitted to a commercial genetic-testing facility demonstrated that the Y chromosome of this African American individual carried the ancestral state of all known Y chromosome SNPs.

Table S1 of the supplementary data provides a list of some of these SNP's, but it is not clear how all this data fits in with the previous y-chromosome phylogeny. Wapondaponda (talk) 09:46, 14 March 2013 (UTC)

 * Does this diagram help? HelenOnline (talk) 10:29, 14 March 2013 (UTC)

Common misconceptions
I notice that the Mitochondrial Eve has a section on common misconceptions. Should we have one here. It might also resolve the notional/unidentified issue.

I have copied the section here and started to amended it as best I can to suit this article. new refs will be required.

 * To generalize: The two articles are conceptually the same and could thus have a more similar structure and content. It would in my mind be an improvement if they did. Lklundin (talk) 08:00, 18 March 2013 (UTC)
 * Yes, that is why I am proposing we add the section below to the article. What do you think? Martin Hogbin (talk) 09:48, 18 March 2013 (UTC)

Not the only man
One of the misconceptions of Y-chromosomal Adam is that since all men alive today descended in a patrilineal from him that he was the only man alive at the time.

that the size of the ancient human population never dropped below tens of thousands???

Other men alive at Adam's time have descendants alive today, but sometime in the past, each of their lines of descent included at least one female, thereby breaking the Y-Chromosomal lines of descent. By contrast, Adam's lines of descent to each person alive today includes precisely one purely patrilineal line.

Not a fixed individual over time
The definition of Y-chromosomal Adam is fixed, but the person in prehistory who will fit this definition can change, not only because of new discoveries, but also because of unbroken father-son lines coming to an end by chance. It follows from the definition of Y-chromosomal Adam that he had at least two sons who both have unbroken lineages that have survived to the present day.

[merge with 'variable Adam']

Not necessarily a contemporary of "Eve"
Sometimes Y-chromosomal Adam is assumed to have lived at the same time as mitochondrial Eve, whom all living people are descended from mattrilineally, perhaps even meeting and mating with her. But this would only be a coincidence. Like, Y-chromosomal "Adam", mitochondrial "Eve" probably lived in Africa; however, according to the latest proposals this "Eve" lived much later than this "Adam" – some 140,000 years later. And earlier studies considered that "Eve" lived earlier than "Adam".

Not the most recent ancestor shared by all humans
Y-chromosomal Adam is the most recent common patrilineal ancestor, not the most recent common ancestor (MRCA).

Since the Y-chromosome is inherited paternally (and recombination is either rare or absent ??), it is relatively easy to track the ancestry of the lineages back to a MRCA; however this MRCA is valid only when discussing the Y-chromosome. An approximate sequence from newest to oldest can list various important points in the ancestry of modern human populations:

 * The Human MRCA. All humans alive today share a surprisingly recent common ancestor, perhaps even within the last 5,000 years, even for people born on different continents.
 * The Identical ancestors point. Just a few thousand years before the most recent single ancestor shared by all living humans was the time at which all humans who were then alive either left no descendants alive today or were common ancestors to all humans alive today. In other words, "each present-day human has exactly the same set of genealogical ancestors" alive at the "Identical ancestors point" in time. This is far more recent than Mitochondrial Eve.
 * Y-chromosomal Adam, the most recent male-line common ancestor of all living people.
 * "Mitochondrial Eve", the most recent female-line common ancestor of all living people, currently appears to have lived long after Y-chromosomal Adam.

 * I am doubtful whether a section on misconceptions is required. The first 3 are already covered in the article and a misconceptions section would duplicate what has already been said. The distinction between Y-chromosomal Adam, most recent common ancestor and Identical ancestors point is worth pointing out, but I think far more briefly as they are not directly relevant, and the links will give interested readers the chance to follow up if they wish.

 * I am particularly dubious about including the mathematical model suggesting a recent common ancestor only a few thousand years ago since, as pointed out here, the authors have not simulated the possibility that there are populations which have been genetically isolated for a long period, so its value is far from clear. Dudley Miles (talk) 23:32, 18 March 2013 (UTC)

true or rather false?
Consider the forth sentence:
 * Some of his male contemporaries have descendants alive today through a mixed male and female line, but none produced a direct, unbroken male line to anyone living today."

Is puting {fact} there ok? — Preceding unsigned comment added by 99.90.197.87 (talk) 15:02, 4 June 2013 (UTC)

< Pattern of threats and insinuations instead facts. If you [Raeky] can use basic math and have source contradicting doi:10.1016/j.ajhg.2013.02.002 talk. 99.90.197.87 (talk) 13:14, 6 June 2013 (UTC)
 * The 2013 study is referenced at the end of the section. Vsmith (talk) 14:08, 6 June 2013 (UTC)
 * Yes it is down below, but. But it does not make, the false sentence, you restore, any more true. Will you argue or explain why (80 =? 300) you deleted the true to restore to false. Perhaps as a time saving compromise, versus deleting all, except one sentence from this section, it will be to rename the section 'Time frame' to History of research. Then the already falsified theses, no longer considered as true science state, may rest, remarked, in the article. As usually some new discoverries invalidate older held conception and the wiki arts should follow. I going to make the changes tomorrow i you have more time or better idea edit or talk.99.90.197.87 (talk) 19:50, 6 June 2013 (UTC)
 * I would agree that the section should be retitled. History of research or something similar would be fine with me. Vsmith (talk) 21:02, 6 June 2013 (UTC)

Talk page should be about truth
Lets be honest with ourselves, I'm not sure I can pull DNA out of a body 100 years in a wooden or pine box, let alone anyone from a dirt sand dune in dry an arid conditions, and I'm at least partially understood that is how you should date mitochondrial cells too? You must compare Adam or Even or Apples or Oranges provided Apples and Oranges are people alive. My factual understanding of this dating process from XY chromosomes is based on mutated cells in a lab and as such should be thrown out or made to admit the science is very strange, to say the least very little of the actual science is reliable. Regarding first peoples these are myths alone an more so they were probably edited by 1850. I have no idea why we are discussing something called Adam or Even or Genesis or anything from a Bible that was handed down for a millennium by word of mouth, made into small texts on parchments and directed into a huge Latin version by 1650, but at least paper existed then and we can't even find those bibles - or if we do the accuracy of the copyright date is not verifiable. I have no regard for this article, I have nothing to contribute than this is absolute bunk or crap. Adam and Even were fictional, and so is the re-creationist versions of mythology including Jesus and the bible - paper did not exist in or around Rome - even if it did it would not survive 80 years on a shelf from the poor quality, and if we don't find a more accurate way of portraying our history, then people that read this are eternally lost and devout to the factual basis of history as it was re-discovered later on written down. Stop inviting history with dates that won't work with any credibility, and continue on with science from today. Leave your calendar alone please. Fatum81 (talk) 01:13, 10 June 2013 (UTC)
 * The names 'Adam' and 'Eve', although taken from the biblical characters, are intended to be somewhat jocular. There is no suggestion that they actually were characters from Abrahamic mythology. Martin Hogbin (talk) 19:54, 10 June 2013 (UTC)

Current edit war
There is an ongoing edit war, relating to external links, but no discussion here. Can someone explain what it is about please. Martin Hogbin (talk) 09:35, 2 September 2013 (UTC)
 * Block evasion - see here for scale. I've semi-protected for a bit. Vsmith (talk) 12:07, 2 September 2013 (UTC)
 * I was more wondering what the objection to the added text was. Martin Hogbin (talk) 15:36, 2 September 2013 (UTC)
 * The ip didn't add text to the article - just external links. I don't see any reason that the Science News article (or the research it was based on) couldn't be used to update the article content. In fact it appears the content is there already based on a different news blurb (current ref #17) in the section: Divergences discovered in 2013 and nomenclature. Vsmith (talk) 16:19, 2 September 2013 (UTC)
 * Fine. Martin Hogbin (talk) 16:48, 9 October 2014 (UTC)

topical tangents over-explaining basics
Every time I visit this page, it seems to be lost in tangents explaining the concept of "MRCA". Most of the time it is also rife with uncaught misconceptions.

The fact that any population has an mrca, and that this mrca will move forward in time as the population itself moves forward in time is a trivial aspect of the definition of mrca and has nothing to do with the topic of "Y-mrca" in particular. It may be helpful for uninformed readers to quickly point them to these relevant facts, but as soon as this article develops entire paragprahs of rhetorics trying to push these points home, it has lost its focus. Any population (just assuming sexual reproduction) has an unambiguous patrilinear mrca. This is the article on research into the time depth of the patrilinear mrca of all currently living humans, with "currently" taking the value of the date of publication of each paper (actually, "currently" just meaning "since we developed the tools to sequence Y chromosomes", assumed ot be negligible over a timescale of the order of 1E5 years).

I realize this page keeps being edited by well-meaning contributors who have not understood what "mrca" even means, but such edits cannot be helpful, and instead of developing the page into a rhetorics piece intended to prevent ill-advised edits (which will never work), it should just be protected against bad edits like any other article on Wikipedia.

tl;dr: this is not the MRCA page, so don't keep trying to explain what the term means! --dab (𒁳) 11:41, 22 January 2015 (UTC)

Those "Other" males living during the time of Adam
Shouldn't be noted that the only source that stated that he wasn't the only male living during his time DOESN'T support the "out of Africa" hypothesis? here: http://mbe.oxfordjournals.org/content/10/1/2.long — Preceding unsigned comment added by 41.45.59.133 (talk) 17:18, 23 January 2015 (UTC)

 * The entire paragraph explaining "there were other males", "the concept is time dependence" is an exercise of clarifying the logical implications of the definition to people unable to understand it if it is just stated. It is legitimate to ask just how far the article should go out of its way to assume the reader is unable to grasp the concept. Revision of this kind of "user service" should be subject to discussion of what is reasonable and adequate.
 * Yet, we still get comments from people apparently thinking that this page is about alleging that there were "other males" living alongside biblical Adam. How can you be clearer than saying "this page has nothing to do with biblical Adam, the name 'Adam' was just used as a joke and then somehow stuck around." There are limits to what this page can achieve in a sane way. I would suggest that the article should just de-emphasize the "Adam" terminology. Of course it should be mentioned, but it should be mentioned as "informal term" and the actual discussion should use "Y-MRCA" or "patrilineal MRCA" to keep this problem as contained as possible. --dab (𒁳) 12:53, 24 January 2015 (UTC)

If those other male contemporaries fail to pass their y-dna SNPs, how could anyone prove they ever existed? it's like tracing someone without any fingerprints or evidence he/she ever existed, btw I am an atheist, I don't care about the Bible or the Coran or whatsoever, so forget about "biblical Adam" and let's try to answer a simple question, how you could prove that there were "other" male homo sapiens sapiens? the article cited a reference that doesn't support the "scientifically proven" out of Africa hypothesis, yet this article "confidently" confirms that there were other male contemporaries? — Preceding unsigned comment added by 41.45.59.133 (talk) 21:31, 24 January 2015 (UTC)
 * It is fortunate you "don't care about the Bible", because this article isn't about the Bible.
 * What you are discussing is the question of the possible human population bottleneck. It is in theory possible that the bottleneck whittled human population down to a single male at some point. But this is extremely unlikely. The definition of Y-MRCA does not exclude this, but the point is that it also doesn't require it, and we are only having this discussion because of the joke name "Adam", not because of any reason connected to the article topic.
 * If there has ever been a "Noah"-like population bottleneck in human prehistory, the human Y-MRCA must be identical to or younger than this individual. In fact, "Adam" was ill chosen, even for the joking reference to biblical genealogy, Y-MRCA of biblical genealogy would be Noah.
 * You also do not show awareness of the fact that Y-Adam is not a fixed individual. Even if there had been a single male alive at some point, whoe would have been the Y-Adam for some time, pedigree collapse would at some later point result in one of his descendants becoming Y-Adam.
 * If you check out the literature on population bottleneck, you will find that estimates of "human population had shrunk to as few as 700 individuals at some point" are the radical ones. This means, the most radical estimates in literature would assume some 350 human males alive at the most precarious reduction of human population ever. Normal speciation takes place without reducing populations to such desperate residues, and the basic assumption is that there have always been populations of at least thousands of individuals ever since Homo diverged from Australopithecus a few million years ago.
 * The population bottleneck article is somewhat related to the "Y-Adam" topic, but the mathematics are far from straightforward. The "long bottleneck" scenario described there (cited to Behar  et al. (May 2008). "The dawn of human matrilineal diversity". American Journal of Human Genetics 82 (5): 1130–40) assumes that there was a population of the order of 2,000 individuals for an extended times. This would mean that there was "always" a population of the order of 1,000 males. This is not "scientifically proven" (this term is not well-formed), it is a scientific estimate for a radical bottleneck scenario. If you can find one that is even more radical, be my guest and cite it. --dab (𒁳) 08:02, 26 January 2015 (UTC)

 * Y-Adam had a father. Next question... This is Wikipedia, not Idiotpedia, when writing we presume a reasonable level of intellectual competence in our readers. Roger (Dodger67) (talk) 22:06, 26 January 2015 (UTC)
 * Wikipedia is also not Snarkypedia. --dab (𒁳) 12:17, 15 March 2015 (UTC)
 * Y-Adam did not have a father of the same species. Simple, different species cannot produce children. Or there was indeed only 2 or 4 people at some point and we can only SEE one or 2 Y chromosomes. Valery Zapolodov (talk) 20:41, 23 December 2021 (UTC)

2015 "bottleneck" paper
Interestingly, the evolution of age estimates looks like this, So we are more or less back were we were 20 years ago. Admittedly, the discovery of a previously unkonwn lineage "A00" is partly responsible for this, but not for all of it. But this is far from definite, I gather that nobody really knows how to calculate these ages because nobody knows the correct mutation rates. In any case, it seems to look as if Y-MRCA was at least as old, if not older than mt-MRCA. Also, it looks as if out-of-Africa migration after about 50 kya was pretty much over, and all non-Sub-Saharans mostly have an Y-MRCA of about that age. --dab (𒁳) 12:17, 15 March 2015 (UTC)
 * 1990s: 200 to 300 kya
 * 2000s: below 100 kya
 * 2010: 120 to 160 kya
 * 2014/5: 200 to 300 kya

This is a nightmare, mt-MRCA estimates seem to become younger, it now seems "current" estimates place mt-MRCA at ~160 kya and Y-MRCA at >200 kya; while some 95% CIs may still overlap, it is misleading to state at this point that age estimates are really "consistent". But estimates are so erratic that it is pretty much a case of wait and see, apparently we still have no stable estimate on either age. --dab (𒁳) 11:03, 23 October 2016 (UTC)

Suggest using same terms
In one place, the article says that humans emerged ".2 to .3 million years ago;" in another place, it says that current thinking is that the Y-MRCA is "about 200,000 years old" (or something like that). I think 200,000 years is the easier term for many readers to understand, so they don't have convert parts of millions of years, so recommend that the estimated age of the Y-MRCA be expressed as hundreds of thousands of years, in numerals.Parkwells (talk) 21:53, 27 March 2015 (UTC)

External links modified
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subscripts
User:Theonlyoxymoron, please explain this edit. Why would you change notation without as much as a hint for your reasons? --dab (𒁳) 10:45, 23 October 2016 (UTC)

living A00 Human
I have the A00, here's my family tree, this should answer a lot of questions.

https://discover.familytreedna.com/y-dna/Q-M242/tree Alphamoses (talk) 15:11, 8 January 2024 (UTC)

title: Talk:Y-chromosomal Adam


text:
Dolichol

Dolichol refers to any of a group of long-chain mostly unsaturated organic compounds that are made up of varying numbers of isoprene units terminating in an α-saturated isoprenoid group, containing an alcohol functional group.

Functions
Dolichols play a role in the post-translational modification of proteins known as N-glycosylation in the form of dolichol phosphate. Dolichols function as a membrane anchor for the formation of the oligosaccharide Glc3–Man9–GlcNAc2 (where Glc is glucose, Man is mannose, and GlcNAc is N-acetylglucosamine). This oligosaccharide is transferred from the dolichol donor onto certain asparagine residues (onto a specific sequence that is "Asn–X–Ser/Thr") of newly forming polypeptide chains. Dolichol is also involved in transfer of the monosaccharides to the forming Glc3–Man9–GlcNAc2–Dolichol carrier.

In addition, dolichols can be adducted to proteins as a posttranslational modification, a process in which branched carbohydrate trees are formed on a dolichol moiety and then transferred to an assembly of proteins to form a large glycoprotein in the rough endoplasmic reticulum.

Dolichols are the major lipid component (14% by mass) of human substantia nigra (SN) neuromelanin. Dolichol phosphate was discovered at the University of Liverpool in the 1960s, although researchers did not know its function at the time of discovery.

Role in aging
Dolichol has been suggested to be used as a biomarker for aging. During aging, the human brain shows a progressive increase in levels of dolichol, a reduction in levels of ubiquinone, but relatively unchanged concentrations of cholesterol and dolichyl phosphate. In the neurodegenerative disease Alzheimer's disease, the situation is reversed, with decreased levels of dolichol and increased levels of ubiquinone. The concentrations of dolichyl phosphate are also increased, while cholesterol remains unchanged. The isoprenoid changes in Alzheimer's disease differ from those occurring during normal aging, and, therefore, this disease cannot be regarded as a result of premature aging. The increase in the sugar carrier dolichyl phosphate may reflect an increased rate of glycosylation in the diseased brain, and the increase in the endogenous anti-oxidant ubiquinone an attempt to protect the brain from oxidative stress, for instance, induced by lipid peroxidation.

Synthesis
Dolichol is a product of the HMG-CoA reductase pathway (also known as the mevalonate pathway), and as such their creation and availability are affected by mevalonate inhibition. First, a cis (or Z) -prenyltransferase (Dehydrodolichyl diphosphate synthase in humans) catalyzes the condensation of farnesyl diphosphate (FPP) with a varying number (dependent on the particular cis-prenyltransferase) of isopentenyl diphosphate (IPP) molecules, resulting in the formation of a polyprenyl diphosphate (also known as dehydrodolichyl diphosphate). This subsequently undergoes loss of both phosphate groups, resulting in a polyprenol (dehydrodolichol). Lastly, the α isoprenoid unit is saturated by α-saturase (still a hypothetical enzyme), and this α-saturated polyprenyl alcohol is known as dolichol.

Other
Dolichols are found in eukaryotes and in archaea, although similar polyprenols molecules are found in bacteria. Polyprenols in bacteria do not contain an α-saturated isoprenoid and are typically smaller in terms of isoprenoid units or carbon length. Polyprenols perform similar functions within bacteria; that is, they function as glycosyl carrier lipids involved in formation of complex branched polysaccharide. However, the cellular process they are involved in is not glycosylation, but instead cell wall biosynthesis. Statins decrease dolichol levels in the body.

Medical significance
The Australian pharmaceutical company Solagran has been investigating the medical significance of polyprenols and their substitution with dolichols when ingested where there is a deficiency. Trials of Ropren (already pharmaceutically registered as a hepatoprotector) in relation to neurodegenerative diseases (including Alzheimer's disease) in both Russia and Australia indicate considerable potential as a safe and effective treatment.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Dolichol