August 25, 2009

Admixture in northeastern Mexico

J Hum Genet. 2009 Aug 14. doi:10.1038/jhg.2009.65.

Ancestry informative markers and admixture proportions in northeastern Mexico

Martinez-Fierro ML, Beuten J, Leach RJ, Parra EJ, Cruz-Lopez M, Rangel-Villalobos H, Riego-Ruiz LR, Ortiz-Lopez R, Martinez-Rodriguez HG, Rojas-Martinez A.

To investigate the ancestral admixture in the Mestizo population in northeastern Mexico, we genotyped 74 ancestral informative markers (AIMs) and 15 Y-single-nucleotide polymorphisms (Y-SNPs) in 100 individuals. The Native American contribution is 56% (range: 27.4-81.2%), the European contribution is 38% (range: 16.7-70.5%) and the West African contribution is 6%. The results show a higher European contribution than was reported in other similar studies in the country, albeit with a predominant Native American ancestry. No remarkable differences in the ancestry proportions were observed using subgroups of 74, 54, 34 and 24 AIMs. The paternal lineage calculated by genotyping of 15 Y-SNPs, shows a major component of European and Eurasian ancestry markers ( approximately 78%), compared with Amerindian ( approximately 12%) and African markers (10%). This information will set a reference for future determinations of admixture proportions in the Mestizo population from Mexico and for population-based association studies of complex diseases.



wolcupitol said...

This didn't sound right, because the African y-dna always comes out as a fraction of the African mtdna, but they're saying the autosomal African ancestry was 6%, while African y-dna was 10%. I was right, here's the list of haplogroups, very limited:

C 0
C3 0
D 0
DE 0,1
E1b1b1b 0
E2 0
G 0,03
I 0,05
J 0,06
K-T 0,02
P 0,28
Q1a3a 0,08
R 0,35
R1a 0,01

They assumed DE as African, when in fact almost all of it is probably Iberian M78 and M123.

Their statement that Indian y-dna was 12% is also strange, since C was 0% and Q was 8%.

And a very strange thing is their finding of P(xQ1a3a,R,R1a) at 28%!?! Since at least 90% of their y-dna is Iberian, and their R results amount to just 35%, I'm presuming almost all of their P samples are in fact R1b.

Anyhow, ho hum, nothing to see here... they should've tested them for SRY2627 or other R1b1b2 subclades, THAT would've made for a notable study...

argiedude said...

Previous post was from me, argiedude.

Maju said...

DE(xD,E1b1b1b,E2) should be other E and in that case should be African. P(xR,Q1a3a) should be other Q and hence Native American. But in that case, I get 36% NA ancestry, not just 12%. R(xR1a) should be R1b indeed.

It would mean that Q(xQ1a3a) was and is very high in NE Mexico, as seems to be the case in other parts of North America.

Thanks for sharing the raw data, Argiedude.