08-05-2010, 10:53 AM
http://leherensuge.blogspot.com/2010/07/...somal.html
Quote:THURSDAY, JULY 22, 2010
New paper on human autosomal phylogenetics
A reader points me to a new quite interesting paper on human phylogeny from the viewpoint of autosomal DNA mainly.
Jinchuang Xing et al. Toward a more uniform sampling of human genetic diversity: A survey of worldwide populations by high-density genotyping. Genomics 2010. Pay per view.
A copy can be found at ZohoViewer and the supplementary material is also freely available.
Abstract
High-throughput genotyping data are useful for making inferences about human evolutionary history. However, the populations sampled to date are unevenly distributed, and some areas (e.g., South and Central Asia) have rarely been sampled in large-scale studies. To assess human genetic variation more evenly, we sampled 296 individuals from 13 worldwide populations that are not covered by previous studies. By combining these samples with a data set from our laboratory and the HapMap II samples, we assembled a final dataset of ~ 250,000 SNPs in 850 individuals from 40 populations. With more uniform sampling, the estimate of global genetic differentiation (FST) substantially decreases from ~ 16% with the HapMap II samples to ~ 11%. A panel of copy number variations typed in the same populations shows patterns of diversity similar to the SNP data, with highest diversity in African populations. This unique sample collection also permits new inferences about human evolutionary history. The comparison of haplotype variation among populations supports a single out-of-Africa migration event and suggests that the founding population of Eurasia may have been relatively large but isolated from Africans for a period of time. We also found a substantial affinity between populations from central Asia (Kyrgyzstani and Mongolian Buryat) and America, suggesting a central Asian contribution to New World founder populations.
Quote:manju said...
Most importantly a clearly distinct South Asian component (purple) has been detected and is strong enough to make up 50% of the Pakistani gene pool and almost the totality of some South Indian populations
Very revealing. Isn't it? Matches with so-called South Asia specific mtDNA in that region. Autosomal analysis is not really helpful. It's a red-herring. We should concentrate on uniparental lineages only to understand linguistic distribution. As I have argued the local matrilineages establish themselves in overall genome over time even when patrilineages keep chaging.
I suppose Newar has only ~25% East Asian patrilineages(compared ~70% South Asian patrilineages). But their matrilineages are predominantly East Asia thus overall they are closer to East Asian.