Talk:Human mitochondrial DNA haplogroup

Graphics
I wrote Mr. Macaulay some time ago and asked him whether I may use their graphics for Wikepedia. He said it is OK as long as he and Mr. Richards are cited.

I uploaded the graphics and used it for the German article on "Mitochondrial Eve". I think it will fit well here.

http://commons.wikimedia.org/wiki/Image:MacaulayRichardsmtDNAtree.jpg

I also made a draft tree depicting the overall structure of the tree. The image of Richards and Macaulay looks very confunsing at first.

http://commons.wikimedia.org/wiki/Image:MtDNAtreeHuman.svg

Molgen 04:40, 10 December 2006 (UTC)

Status of L1 and L3
Perhaps we should state more clearly that L1 and L3 are no real (=monophyletic) haplogroups. Haplogroup L1a is not closer related to L1f as it is to V.

Molgen 04:40, 10 December 2006 (UTC)

Definition of mtDNA haplogroups
What is the definition of each of the mtDNA haplogroups? I.e. by which mutation it characterized? --Maruvkay 03:50, 13 August 2006

Your chart is a bit wrong. L2 comes from L1/L0 and L3 comes from L2.

L1 -> L2 ->L3 https://www3.nationalgeographic.com/genographic/

Mitochondrial Eve: The Mother of Us All

Ancestral Line: "Mitochondrial Eve"

Our story begins in Africa sometime between 150,000 and 170,000 years ago, with a woman whom anthropologists have nicknamed "Mitochondrial Eve."

She was awarded this mythic epithet in 1987 when population geneticists discovered that all people alive on the planet today can trace their maternal lineage back to her.

But Mitochondrial Eve was not the first female human. Homo sapiens evolved in Africa around 200,000 years ago, and the first hominids—characterized by their unique bipedal stature—appeared nearly two million years before that. Yet despite humans having been around for almost 30,000 years, Eve is exceptional because hers is the only lineage from that distant time to survive to the present day.

Which begs the question, "So why Eve?"

Simply put, Eve was a survivor. A maternal line can become extinct for a number of reasons. A woman may not have children, or she may bear only sons (who do not pass her mtDNA to the next generation). She may fall victim to a catastrophic event such as a volcanic eruption, flood, or famine, all of which have plagued humans since the dawn of our species.

None of these extinction events happened to Eve's line. It may have been simple luck, or it may have been something much more. It was around this same time that modern humans' intellectual capacity underwent what author Jared Diamond coined the Great Leap Forward. Many anthropologists believe that the emergence of language gave us a huge advantage over other early human species. Improved tools and weapons, the ability to plan ahead and cooperate with one another, and an increased capacity to exploit resources in ways we hadn't been able to earlier, all allowed modern humans to rapidly migrate to new territories, exploit new resources, and outcompete and replace other hominids, such as the Neandertals.

It is difficult to pinpoint the chain of events that led to Eve's unique success, but we can say with certainty that all of us trace our maternal lineage back to this one woman.

The L Haplogroups: The Deepest Branches

Ancestral line: "Eve" > L1/L0

Mitochondrial Eve represents the root of the human family tree. Her descendents, moving around within Africa, eventually split into two distinct groups, characterized by a different set of mutations their members carry.

These groups are referred to as L0 and L1, and these individuals have the most divergent genetic sequences of anybody alive today, meaning they represent the deepest branches of the mitochondrial tree. Importantly, current genetic data indicates that indigenous people belonging to these groups are found exclusively in Africa. This means that, because all humans have a common female ancestor, "Eve," and because the genetic data shows that Africans are the oldest groups on the planet, we know our species originated there.

Haplogroups L1 and L0 likely originated in East Africa and then spread throughout the rest of the continent. Today, these lineages are found at highest frequencies in Africa's indigenous populations, the hunter-gatherer groups who have maintained their ancestors' culture, language, and customs for thousands of years.

At some point, after these two groups had coexisted in Africa for a few thousand years, something important happened. The mitochondrial sequence of a woman in one of these groups, L1, mutated. A letter in her DNA changed, and because many of her descendants have survived to the present, this change has become a window into the past. The descendants of this woman, characterized by this signpost mutation, went on to form their own group, called L2. Because the ancestor of L2 was herself a member of L1, we can say something about the emergence of these important groups: Eve begat L1, and L1 begat L2. Now we're starting to move down your ancestral line.

Haplogroup L2: West Africa

Ancestral line: "Eve" > L1/L0 > L2

L2 individuals are found in sub-Saharan Africa, and like their L1 predecessors, they also live in Central Africa and as far south as South Africa. But whereas L1/L0 individuals remained predominantly in eastern and southern Africa, your ancestors broke off into a different direction, which you can follow on the map above.

L2 individuals are most predominant in West Africa, where they constitute the majority of female lineages. And because L2 individuals are found at high frequencies and widely distributed along western Africa, they represent one of the predominant lineages in African-Americans. Unfortunately, it is difficult to pinpoint where a specific L2 lineage might have arisen. For an African-American who is L2—the likely result of West Africans being brought to America during the slave trade—it is difficult to say with certainty exactly where in Africa that lineage arose.

Fortunately, collaborative sampling with indigenous groups is currently underway to help learn more about these types of questions and to possibly bridge the gap that was created during those transatlantic voyages hundreds of years ago.

Haplogroup L3: Out of Africa

Ancestral line: "Eve" > L1/L0 > L2 > L3

Your next signpost ancestor is the woman whose birth around 80,000 years ago began haplogroup L3. It is a similar story: an individual in L2 underwent a mutation to her mitochondrial DNA, which was passed onto her children. The children were successful, and their descendants ultimately broke away from the L2 clan, eventually separating into a new group called L3. You can see above that this has revealed another step in your ancestral line.

While L3 individuals are found all over Africa, including the southern reaches of sub-Sahara, L3 is important for its movements north. You can follow this movement of the map above, seeing first the expansions of L1/L0, then L2, and followed by the northward migration of L3.

Your L3 ancestors were significant because they are the first modern humans to have left Africa, representing the deepest branches of the tree found outside of that continent.

Why would humans have first ventured out of the familiar African hunting grounds and into unexplored lands? It is likely that a fluctuation in climate may have provided the impetus for your ancestors' exodus out of Africa.

The African Ice Age was characterized by drought rather than by cold. Around 50,000 years ago the ice sheets of northern Europe began to melt, introducing a period of warmer temperatures and moister climate in Africa. Parts of the inhospitable Sahara briefly became habitable. As the drought-ridden desert changed to savanna, the animals your ancestors hunted expanded their range and began moving through the newly emerging green corridor of grasslands. Your nomadic ancestors followed the good weather and plentiful game northward across this Saharan Gateway, although the exact route they followed remains to be determined.

Today, L3 individuals are found at high frequencies in populations across North Africa. From there, members of this group went in a few different directions. Some lineages within L3 testify to a distinct expansion event in the mid-Holocene that headed south, and are predominant in many Bantu groups found all over Africa. One group of individuals headed west and is primarily restricted to Atlantic western Africa, including the islands of Cabo Verde.

Other L3 individuals, your ancestors, kept moving northward, eventually leaving the African continent completely. These people currently make up around ten percent of the Middle Eastern population, and gave rise to two important haplogroups that went on to populate the rest of the world.

Why no O, P or S groups?
What was the reason behind the classification to omit the sequence O, P & S from being the names of mtHaplogroups? Also, why is the earliest group designated 'L'? The Y-chromosome Haplogroups are much more intuitive in sequence, starting at 'A' and going from there. The classifying letters in the mt-Haplogroups seem to jump around more from a evolutionary/mutation-rate to label perspective. Whatever the reasoning is, it might be beneficial to have some explaination of it in the article Nagelfar 11:01, 18 January 2007 (UTC)
 * OK, I added the Haplogroup P link since there was already a page for it, but it still doesn't appear on the table of mt Haplogroups. Nagelfar 18:56, 28 January 2007 (UTC)
 * OK, found the template page (finally figured out how to edit those), added P, it's here; Template:MtDNA. Someone who knows needs to find the placement of O & S, and maybe help by starting those pages too. Nagelfar 02:12, 11 February 2007 (UTC)
 * Finally added them, though I really know nothing about the O group. Nagelfar 19:38, 15 April 2007 (UTC)

Please! There are no mtDNA haplogroups S nor O, AFAIK. If you know nothing of genetics why do you mess up?

The names for mtDNA lineages are, as you say, non-intuitive due to historical reasons (among them less interest and research in mtDNA than in Y-DNA, plus a quite Eurocentric approach initially) and many of these haplogroups are quite messy. Y-DNA nomenclature was homogeneized in 2001 and is continually reviewed by a single (consensually accepted) entity (YSOGG), there is nothing of the kind for mtDNA and that makes things somewhat more complicated. --Sugaar (talk) 17:03, 5 March 2008 (UTC)


 * Admitedly it seems there is a haplogroup S (I didn't know). But still why you created the page for non-existent haplogroup O, knowing that it might not exist after all? I have nominated it for speedy deletion. --Sugaar (talk) 17:13, 5 March 2008 (UTC)


 * So there's A-Z sans O? There's just little reference for it, but if there's a citation for there being no mtDNA "O" write that into the mtDNA haplogroup article to substantiate that, I am simply laying the groundwork for the whole strata of human haplogroups and in the process of doing so there will need to be work that should be filled in by others, getting upset about it or making ad hominem accusations (i.e. "know nothing") won't bring any progress, a rule to wikipedia is be bold. Nagelfar (talk) 09:59, 10 April 2008 (UTC)

mtDNA Haplogroups O, P, and S Now Exist!
Please see Phylotree V14. (http://www.phylotree.org) For that matter, haplogroup S existed way back in 2007 well before the deletions of 2008. See: http://www.pnas.org/content/104/21/8726.full Now, could we please kindly have the respective articles reinstated? --RebekahThorn (talk) 01:35, 11 May 2012 (UTC)

Proposal to create a new WikiProject: Genetic History
I have put up a suggestion at Wikipedia:WikiProject Council/Proposals to create a new WikiProject, WikiProject: Genetic History.

To quote from what I've written there:


 * Description: A wikiproject for articles on DNA research into genetic genealogy and genealogical DNA tests; the history and spread of human populations as revealed by eg human Y-chromosome and mitochondrial DNA haplogroups; and similar. Many such articles can be found in Category:Genetic genealogy and its subcategories, notably the subcategories on human haplogroups.


 * Rationale
 * My direct motivation for seeking this Wikiproject was a recent run-in at Y-chromosomal Aaron, where I desperately missed the lack of a relevant WikiProject talk page to go to, to attract the input, advice and views of knowledgeable editors in this area.
 * There's a lot of general public interest in the proposed subject area -- eg the Y-chromosomal Aaron page is apparently getting well over 100 hits a day, and over the last 18 months or so there's been a lot of material added, by a fair number of different editors, mostly editing different pages which are particularly relevant to them. IMO, a central wikiproject would be useful, and also a good place to be able to bring WP:OR, WP:V, and WP:general cluelessness issues for wider informed input.
 * Wikipedia:WikiProject Molecular and Cellular Biology and Wikipedia:WikiProject Evolutionary biology do already exist, but their focus is much much broader. With regard to those project's charters, I believe the subject would be seen as a rather specialist niche topic area, rather out of the mainstream of those project's normal focus.  On the other hand, I believe that there are a number of wikipedia editors (and readers) who are specifically interested in the subject, who would find advantage if there were a specific wikiproject for it. Jheald (talk) 12:56, 22 February 2008 (UTC)

If people think this would be a good idea, it's a target for WikiProjects to have at least five "interested" signatures to show there's some support, before they get going.

Alternatively, if people think it would be a bad idea, please leave a comment in the comments section.

Either way, please show what you think, at Wikipedia:WikiProject_Council/Proposals

Thanks, Jheald (talk) 13:29, 22 February 2008 (UTC)

Status of K. It's a subclade of U8.
As per A. González et al., 2006 (The mitochondrial lineage U8a reveals a Paleolithic settlement in the Basque country), and probably other papers I am not aware of, K is a subclade of U8 (closer to U8b than U8a). See Figure 1 of that paper.

I strongly suggest to reposition it in this article as in the mtDNA template. The convention nowadays is that there is no "haplogroup UK" anymore but just haplogroup U of which K is a second or third level subclade, even if a quite common one. --Sugaar (talk) 16:34, 5 March 2008 (UTC)

Map
I forget what kind of projection the first map is done with, but it should be labeled as such - it took me some ponderance to figure out what it was, and I've seen it before. Dextrose (talk) 03:17, 27 July 2008 (UTC)

Will someone please include photos of people from each mtdna haplogroup?
I would certainly like to see examples of each mtdna haplogroup. I just took a DNA ancestry test. And I got a very unexpected out haplogroup. Which might explain why I look so different from everyone in my town.

- signed Purple Thunder —Preceding unsigned comment added by 75.54.81.188 (talk) 18:02, 12 March 2009 (UTC)


 * Except in rare cases such as bushmen (LO), papuans (Q), some siberians (G & Y) or malayans (E), it's not a good idea to try to identify haplogroups by means of photographs because most of the human being groups have come out of the mixture of many different haplogroups. This is why no picture would be accurate. --Maulucioni (talk) 16:24, 6 June 2009 (UTC)

Diagramatic and lineage perspectives do not agree
For instance, the lineage perspective shows L2 as a subclade of L1, but the diagram shows L2 and L1 as being co-subclades of Mt-Eve. --Michael C. Price talk 06:39, 20 May 2009 (UTC)

Misleading definition of mtEVE
The text says she is the matrilineal mrca. Most lay readers (methinks) would interpret this as meaning she is the most recent female ancestor; eg the most recent woman who was ancestor (in whatever line) to all living humans. Would it be okay to add a sentence to clarify her status; or alternatively delete "matrilineal" and add "ancestor of the mitochondria of all living humans" near the end of the sentence? 84.59.254.134 (talk) 17:09, 21 October 2009 (UTC)

Citing a source would also be nice, seeing as this article has only 2 sources cited. 2602:306:C4EF:2BA0:5076:566F:FA8C:F2A2 (talk) 05:33, 11 May 2015 (UTC)

Please list the characteristic mutations that define each haplogroup
The article could be improved by listing the characteristic mutations, ie, what distinguishes N from M, etc. This information could then be used in other articles. This information is present for the Y-dna haplogroups. Skates61 (talk) 09:43, 15 March 2010 (UTC)

New section
The european genetics is only a small subgroup of the World's genetics. The new section Chronological development of haplogroups about European haplogroups should not be here, but in the Genetic history of European populations article. It must be move it. --Maulucioni (talk) 00:08, 25 October 2010 (UTC)

Established science?
Are the migration location established science or the speculations of a single book author? 84.227.246.65 (talk) 18:46, 16 July 2014 (UTC)

image
http://nadge.org/wp-content/uploads/2009/08/mtDNA-Y-Migration-Map-Spencer_Wells2-1024x524.jpg

I eventually cancelled the sentence " Furthermore, attributing a specific geographic origin to any haplogroup, such as those proposed in the table below, is highly speculative and considered by most population geneticists to be 'story telling' and outside the domain of science.", because it would even render the "Out of Africa"-hypothesis outside science!217.93.140.13 (talk) 15:52, 1 January 2016 (UTC)

Mitochondrial DNA haplogroup
It is unclear why the topic of "Mitochondrial DNA haplogroup" redirects to "Human mitochondrial DNA haplogroup" because these are found in other species. William Harris •   talk •   07:36, 12 July 2016 (UTC)

Hypothetical Woman?
Why does the description say "The hypothetical woman at the root of all these groups "... in what way is she "hypothetical". there has to be such a person. no hypothetical about it. Unless there's a rationale for this word I plan to strike it. Skates61 (talk) 22:44, 27 March 2023 (UTC)