Talk:Haplogroup M (mtDNA)
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A few comments
With regard to M origins, I think there should be some levity on the various sides here. M evolved from some aspect of L3, unless someone is arguing for some sort of recombination between N and asiatic hominids. proto M did not evolve in South Asia. There are several possible options that have not been considered. The previous interglacial cycle may have presented opportunities in the Sahara just as the climate optimum did after all we do see almost modern humans in the Levant between 115 and 135 kya. So it is possible that M lineages formed in NE africa during the previous interglacial, and was flushed into Asia after that period of time leaving north Africa largely vacated except proto-M1. Alternatively L3 might have made it to the Arabia or the levant, given rise to N and M lineages during a climate optimum for some region through drift M and N moved on and L3 was lost. Consider what the problems are here, the dating of M lineage at 65 to 80 kya, depending on how one does ones math, has a rather large variance. During that variance period one has the previous interglacial, mt Toba eruption, etc. L3 has other branches in Africa, including South Africa to Mauritania. Most of the other branches are bushy at the base branch, except M and N which suggest both had been in slight isolation for a period of time prior to expansion.
Here is the principle argument from Asia origin, if L3 is african and M is Asian, and there are 4 mutations between L3 and M, then those 4 mutations could have formed between east Africa or India. But if all four formed in East Africa, it would mean that the transit time between east Afria and India was less than 5000 years, otherwise M mutations would have formed along the way. If the model of migration is tolerant of migration between East Africa and India of less than 5000 years there is no essential conflict between African or Asian origins, either could be true because if there is a constraint on population size L3 evolves to M in situ or along the way, either way ancestral mutation is fortuitiously lost. Any branch point found between L3 and M essentially anchors the arguement. The likelihood of finding new branchpoints in Asia is rather low, but much higher in Africa. The claim is that M left Africa between 70 and 80 kya, the oldest archaeological sites are Eastern India (~76 kya) and LiuJiang (~70kya for youngest date), so yeah, M could have left africa and traveled to India in 5000 years, and yeah there could be a founder affect as the sites are about the same date but spread widely.
Question: is it so important whether M evolved in Africa or Asia, these are constructs that seem important to us, but if we look at gene flow, the sahara is as big a genographic barrier compared to the boundary between North Africa and Western Europe, and there is no boundary once cultures reach the lower nile, beach combers can reach anatolia within a few days walking. The driving distinction here is between the split boundaries between N and M. By my gene barometer this is somewhere around Pakistan and Iran, anything that can make it east of the Indus early in human evolution is likely to spread much farther eastward. That is a rather huge region (between SSA and the Indus) for genes to waffle back and forth with transmigration or climate ossillations.
My answer: the main wastes entirely too much time on M's origin, what percent of people in Africa have been typed for mtDNA? Tiskoff focused on one country in Africa and found a brand new and deep branch of L1 lineages (L5). What is the probability that when Angola is typed or more typing in Congo we will find new mtDNA lineages. There is no need to draft an assumption that there is only M1 in africa and no other M versions, some very deeply branching clades in Africa are very local in their distribution. It is possible that post L3 proto M lineages still exist in Africa, the same is true for N. Albeit if M1 did originate in Europe or Asia I would not be surprised either, since there has been gene from from Iberia into Africa during the prehistoric period. Here is the basic philosophical question- Throw a coin in the air, and call heads or tails before it hits the ground, it all makes good statistics, but that is not how science should present its results to the general public. Science should strive to call the coin once it is settled on the turf-this coin is in mid flight, while its in mid flight - cut though all the crap quickly and say - we don't know, very simple, three words. Some words of wisdom here about calling coins in the air, in an area such as equitorial Africa, where huge regions have had roughly stable climate for 10,000s of years its easier to make certain predictions, but when one deals with increasing probabilities of migrations via north Africa or Arabia, including the regions immediately south of the Sahara, one is dealing with a tempest, a wild card in the game, climate change. The rapid change in climate following periods of nomadic opportunities in the Sahara act to draw peoples into North African and then expell them or eliminate them. One cannot always predict where or how fast they would be expelled.
I also want to critique one specific point. Appearance of diversity is not always represented by divergence time. This is a common misconception in the literature, divergence times are largely determined by the 2N rule, and then 2N rule basically argues that as populations (or cohesive subpopulations) coalesce on a single point that the population size must have been such that previous branching was eliminated by drift. There is no known aspect of human population that converges on a single point and highly unlikely (microscopically low probability) that it could converge on 2 individuals. Therefore loss of lineages, such as intermediate branchpoints are evidence of population constraints (i.e the size of the population versus the frequency of an allele versus the length of the timeframe], particularly in lineages like M1 (mutations:195,6446,6680, 12403,12950C,14110,16249,16311 [I eliminated two hypermutations] has 8 mutations, which is about 40,000 years with no evidence of branching. In this way certain lineages, for example the L5 lineages and certin L0 lineages have remained constrained with few branch points and very long spans between branch points. Populations in their local areas have remained constrained in size since these lineages appeared, such long lineages are particularly common in Africa which in some areas have had very long periods of constrained growth. Short branch lengths are a characteristic of Eurasia and many examples of growth. The presence of diversity in India and the oldest lineages in bangledesh is almost a trivial assertion when one knows the base of the M lineages is African L3 + a handful of mutations. The only thing that this asserts is that M had more opportunities for growth (as founder affects ussually do), and its rapid growth. Consider that a new mutation happens in mtDNA lineage once every 5000 years, that is 250 generations, if one increases the population size from 1 to say 1000 one is more likely to observe a new variant in a single generation if it expands to 10,000 individual there is a good chance of 20 or so different mutants, if the population remains at 1 however, any mutation that occurs is either fixed or lost and the diversity is 0. The more individuals, the more diversity. Whenever there is a founder affect and diversification, its like the universe, all reference points are valid. M lineages did not evolve from someone in Bangledesh leaving no trace of L3 behind. Contrasting M1 with Indian M the difference is that where-ever M1 was, the carrying capacity was much lower, and lower prospects for expansion, compared with the other M lineages, which is revealled over and over again, landed in a place with a great potential for expansion.
The use of M divesity as a citation of more advanced age than M1 when it may have been the only or dominant haplogroup in a founder affect is misleading and the claim of age for M lineages in Bangledesh as being the oldest in India is, in fact, a distortion.PB666 yap 05:13, 10 September 2009 (UTC)
- The thing is that we are restrained to use the scientific literature and not our own ideas on these things. Expecting that people will not want to mention what it says about possible places seems unrealistic, so if it needs to say something, then it needs to say what has been published.--Andrew Lancaster (talk) 06:02, 10 September 2009 (UTC)
- Though Pdeitiker is not sympathetic to current models of the Out of Africa theory, I agree with much of what he has said. Whether M originated in Africa or Asia is not important, it is too far back in time and the various possibilities and permutations of what could have happened are too vast for the exact origins to ever be determined. However the philosophy prevalent on blogs that the exact location of origin of a haplogroup carries some special value has been brought to these articles. My interest here has not been to prove that this lineage originated in certain place, but that it is possible that it could have originated in certain areas.
- With regard to OOA, one issue that is still very controversial is dating the presence of Anatomically Modern Humans outside Africa. Though humans were in Israel circa 100kya, all other evidence of AMH outside Africa from similar time frames is shaky. I have trying to find information from India and Arabia, and at present the evidence is highly inconclusive. Wapondaponda (talk) 08:23, 10 September 2009 (UTC)
New study, Chandrasekar et al 2009
Updating Phylogeny of Mitochondrial DNA Macrohaplogroup M in India: Dispersal of Modern Human in South Asian Corridor Discusses the origin of haplogroup M. The study acknowledges that the origin of the haplogroup is indeterminate, but doesn't rule out an Indian origin. This can be contrasted with Abu-Amero 2009, which posits an Arabian origin of these haplogroups. Wapondaponda (talk) 12:48, 13 October 2009 (UTC)
haplogroup M1 and M51
According to the tree published at phylotree, East African haplogroup M1 and Indian haplogroup M51 form a monophyletic clade united by the mutation 14110. This is based on Hartmann et al. (unfortunately subscription is needed for the full article). It remains to be seen whether 14110 in both these lineages is as a result of parallel mutations or common ancestry. Some parallel mutations in M1 and other M lineages were suggested by sun et al., examples include 16311 for M4 and 16129 for M5. However if 14110 indicates common ancestry between m1 and m51, then this would provide major support for the Asian origin hypothesis. Not only the Asian origin, but it would also provide support for an ultimate Asian origin of proto-Afroasiatic speakers. Surprisingly a discussion of this connection has not yet been published. Wapondaponda (talk) 13:25, 27 February 2010 (UTC)
Orphaned references in Haplogroup M (mtDNA)
I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Haplogroup M (mtDNA)'s orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.
Reference named "Wen2004":
- From Koreans: Bo Wen, Hui Li, Daru Lu et al., "Genetic evidence supports demic diffusion of Han culture," Nature, Vol 431, 16 September 2004
- From Haplogroup F (mtDNA): Bo Wen, Xuanhua Xie, Song Gao et al., "Analyses of Genetic Structure of Tibeto-Burman Populations Reveals Sex-Biased Admixture in Southern Tibeto-Burmans," Am. J. Hum. Genet. 74:856–865 (2004)
I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT⚡ 05:13, 27 October 2013 (UTC)
Found this:""When I go to Wikipedia mtDNA M site, I see that M10 and M42 are grouped together under M10’42, and M74 has disappeared".
Human migrations and mitochondrial haplogroups map
The "human migrations and mitochondrial haplogroups" map appears to be inaccurate. Its shading suggests that certain geographic regions are overwhelmingly defined by specific haplogroups, which oftentimes isn't the situation at all. There is instead typically an assortment of haplogroups per region. Its shading simultaneously implies that macrohaplogroup M and other clades are exclusive to certain regions, which is also inaccurate for the same reason. A number of M's sub-clades actually have postulated origins outside of the highlighted South Asian, Northeast Asian and South American areas. Soupforone (talk) 00:26, 6 May 2014 (UTC)