Continuing with the "American Neanderthals"... I took another look at the map showing the B006 haplotype in the X chromosome which I had posted in my previous entry, and was surprised to notice that there is a high "density" of this mutation in the Indian Subcontinent.
So I focused on the regions with high concentration of this haplotype and marked them on the map, which you can see below:
Worldwide distribution of B006 haplotype based on a worldwide sample of 6092 X chromosomes. Areas with high percentage are highlighted . From [1]
As you can see, there are three areas within America that have a high density of B006 mutation:
1. Amazon: northern Bolivia, south western Peru and western Brazil. A relatively out of the way place, which due to its isolation could account for a high ratio of a rare mutation.
2. Meso America and northwestern South America, from Colombia to Yucatan.
3. Western Canada and the US (British Columbia, Oregon, Washington and California. (The "odd" Yuki live in California).
4. Europe excluding the Balkans and Southern Italy.
5. Indian Subcontinent.
The Indian Subcontinent's oddity
Why India and Pakistan? The map shows that the percentage of humans with B006 mutation drops off as you move out of Europe into Asia and across Asia (in China it drops to 0% of the population).
It picks up in Beringia and increases dramatically in America.
But, why so high in the Indian Subcontinent (yes, I also saw the Australian increase after dropping off to zero in Indonesia. What can that mean? Perhaps the "Kow Swamp" people took it there: they were robust hominids which survived until about 10,000 years ago in Australia, co-existing with modern humans).
Getting back to India and Pakistan. I recalled that I had posted about another mutation in the X chromosome known as RRM2P4.
It is rare in Africa and so it is probably of non-African origin or, belongs to some group that moved out of Africa with it (where it later disappeared) and passed it back into the modern human lineage (this is known as "introgression"),
So I decided to take a look at the data on RRM2P4, and came across a Table from [2] shown below:
Table 1. Shows RRM2P4 sequence in different populations. From [2]
I was expecting American sequences to resemble Western Asian ones (after all that is where the Amerindians are supposed to have come from), but no. No similarity whatsoever.
The only Asian sequence that is identical to American ones, is from Pakistan.
So here we have a link between: Pakistan and America with an X chromosome mutation RRM2P4 and the previous one, another mutation in the X chromosome (B006) linking America and the same region of the Indian Subcontinent.
Two links that completely by-pass the rest of Asia that lies between Pakistan/India and America.
Both in an X chromosome, one which we all inherit from our female ancestors (if you are a man, your X chromosome is your mother's and your Y is your father's. If you are a woman, you got an X from your mom and another X from your Dad, but his came from his mom - your paternal grandmother).
So this means that these mutations introgressed into the human (H. sapiens) lineage from Female H. erectus or Neanderthals.
But is there any other linkage between both regions?
O blood allele, as I mentioned in my previous post has been linked to Neanderthals and, has its highest frequencies in America. Most of Western Asia has relatively low ratios of O allele, and B is predominant (you would expect the opposite if Asia was the cradle of Amerindians).
But, surprisingly, a study indicates that O blood group is higher in Sindh and Baluchistan (Southern Pakistan), see table below from [3]:
And the data from [4] indicates that in eastern Pakistan, just above Sindh the percentage of O allele is even higher, as it ranges from 54& to 57.6% (Punjab, Gujrat and Wah Cant).
In India, the area just east of those mentioned in Pakistan, have a very strange blood group, the "O Bombay Blood Group", first discovered there, and found in about 1 every 17,600 persons in India.
It is found on the western coast of India and in Maharashtra, Gujrat (India) Karnataka, Goa and Andhra Pradesh.
So we have a higher percentage of O allele in this part of the world, and, a strange variety found only here!.
Sources:
[1] Yotova et al., (2011). An X-linked haplotype of Neandertal origin is present among all non-African populations 25.01.11.
[2] Michael F. Hammer, Daniel Garrigan, Elizabeth Wood, Jason A. Wilder, Zahra Mobasher, Abigail Bigham, James G. Krenz and Michael W. Nachman, (2004), Heterogeneous Patterns of Variation Among Multiple Human X-Linked Loci, The Possible Role of Diversity-Reducing Selection in Non-Africans.
doi: 10.1534/genetics.103.025361 Genetics August 1, 2004 vol. 167 no. 4 1841-1853
[3] Imranud Din Khattak, Taj Muhammad Khan, Purdil Khan, Syed Mukhtar Ali Shah, Sania Tanveer Khattak, Anwar Ali. (2008). J Ayub Med Coll Abbottabad 2008;20(4). Frequency of ABO and Rhesus blood groups om district Swat, Pakistan
[4] Mohammad Anees and Mohammad Shabir Mirza, (2005). Distribution of ABO and RH Blood Group Alleles in Gujrat Region of Punjab, Pakistan Proc. Pakistan AcaMd.. SAcnie.e s4 2&(4 M):.2 3S3ha-2b3ir8 M.2i0rz0a5
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia
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