From: mkelkar2003
Message: 41882
Date: 2005-11-08
>Please refer to message # 41875 for a detailed critique of Bamshad
> Reading the paper that has been cited in several postings:
> <http://www.genome.org/cgi/content/abstract/11/6/994>
>
> I'll copy it to make it simple:
> Genetic Evidence on the Origins of Indian Caste Populations
> Michael Bamshad,1,10,12 Toomas Kivisild,2 W. Scott Watkins,3 Mary E.
> Dixon,3 Chris E. Ricker,3 Baskara B. Rao,4 J. Mastan Naidu,4 B.V. Ravi
> Prasad,4,5 P. Govinda Reddy,6 Arani Rasanayagam,7 Surinder S. Papiha,8
> Richard Villems,2 Alan J. Redd,7 Michael F. Hammer,7 Son V. Nguyen,9
> Marion L. Carroll,9 Mark A. Batzer,9,11 and Lynn B. Jorde3
>
> 1 Department of Pediatrics, University of Utah, Salt Lake City, Utah
> 84112, USA; 2 Institute of Molecular and Cell Biology, Tartu
> University and Estonian Biocentre, Tartu 51010, Estonia; 3 Department
> of Human Genetics, University of Utah, Salt Lake City, Utah 84112,
> USA; 4 Department of Anthropology, Andhra University, Visakhapatnam,
> Andhra Pradesh, India; 5 Anthropological Survey of India, Calcutta,
> India; 6 Department of Anthropology, University of Madras, Madras,
> Tamil Nadu, India; 7 Laboratory of Molecular Systematics and
> Evolution, University of Arizona, Tucson, Arizona 85721, USA; 8
> Department of Human Genetics, University of Newcastle-upon-Tyne, UK; 9
> Department of Pathology, Biometry and Genetics, Biochemistry and
> Molecular Biology, Stanley S. Scott Cancer Center, Louisiana State
> University Health Science Center, New Orleans, Louisiana 70112, USA
>
> The origins and affinities of the ~1 billion people living on the
> subcontinent of India have long been contested. This is owing, in
> part, to the many different waves of immigrants that have influenced
> the genetic structure of India. In the most recent of these waves,
> Indo-European-speaking people from West Eurasia entered India from the
> Northwest and diffused throughout the subcontinent. They purportedly
> admixed with or displaced indigenous Dravidic-speaking populations.
> Subsequently they may have established the Hindu caste system and
> placed themselves primarily in castes of higher rank. To explore the
> impact of West Eurasians on contemporary Indian caste populations, we
> compared mtDNA (400 bp of hypervariable region 1 and 14 restriction
> site polymorphisms) and Y-chromosome (20 biallelic polymorphisms and 5
> short tandem repeats) variation in ~265 males from eight castes of
> different rank to ~750 Africans, Asians, Europeans, and other Indians.
> For maternally inherited mtDNA, each caste is most similar to Asians.
> However, 20%-30% of Indian mtDNA haplotypes belong to West Eurasian
> haplogroups, and the frequency of these haplotypes is proportional to
> caste rank, the highest frequency of West Eurasian haplotypes being
> found in the upper castes. In contrast, for paternally inherited
> Y-chromosome variation each caste is more similar to Europeans than to
> Asians. Moreover, the affinity to Europeans is proportionate to caste
> rank, the upper castes being most similar to Europeans, particularly
> East Europeans. These findings are consistent with greater West
> Eurasian male admixture with castes of higher rank. Nevertheless, the
> mitochondrial genome and the Y chromosome each represents only a
> single haploid locus and is more susceptible to large stochastic
> variation, bottlenecks, and selective sweeps. Thus, to increase the
> power of our analysis, we assayed 40 independent, biparentally
> inherited autosomal loci (1 LINE-1 and 39 Alu elements) in all of the
> caste and continental populations (~600 individuals). Analysis of
> these data demonstrated that the upper castes have a higher affinity
> to Europeans than to Asians, and the upper castes are significantly
> more similar to Europeans than are the lower castes. Collectively, all
> five datasets show a trend toward upper castes being more similar to
> Europeans, whereas lower castes are more similar to Asians. We
> conclude that Indian castes are most likely to be of proto-Asian
> origin with West Eurasian admixture resulting in rank-related and
> sex-specific differences in the genetic affinities of castes to Asians
> and Europeans. (end copy)
>
> Doesn't an admixture of European-like chromosomes in the higher
> castes of India point to the ancestors thereof being intrusive; and
> moreover that this shows in the male rather than female chromosomes,
> not simply immigrants, but invaders?
> Is there any other reasonable interpretation?
> Dan
>