Talk:Genetics and Archaeogenetics of South Asia
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Why is no one talking of sample size and sampling strategy of all the studies that have been done? MOst of these studies are poor in terms of design and not much generalisations can be made from them.== Tocharians == This article probably could benefit from some reference to (or at least a link to) the Tocharian people [1]
Borderline if they can be included in the "south asia concept" but as india seems to belong here, and the Tocharians probably had some contact there on their way to the east of China....
Even if they did or did not in the end contribute many genes they can stand as an example of the migrations from Europe to Asia that were taking place. And it's nice that we have physical relics of them, mummies and colour depictions.
Then there are the genetics of the Berber people and the Guanche People, who also seem to have had that funny looking yellow hair and seem to have been lodged outside their normal realm, but they are in africa hence by far outside the scope of this article.
Would take a shot at it myself if I were not so lazzzzy.
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[edit] Removed copy from Bamshad et al. study
A user 71.195.221.190 has copied a large portion from Bamshad et al. study. This is irrelevent here as the it was just one of the studies also the first one to explore it. The details of the study has been included under mtDNA and Y-chromosome headings. In fact, many of the data from the study is patently incorrect, such as mtDNA U2i as proved by the later Kivisild et al. study(2003). So we don't have to consider that primitive study as the final word on caste genetics.
Manjunatha (23 Apr 2006)
[edit] Removed the following:
It is certainly agreed upon by most antoropologists that most Indians, whether "Dravidian" or "Aryan" are still members of the Caucasiod race as per their skull-structure and genes.
Egon Freiherr von Eickstedt Template:Von E. Eickstedt racial definitions
--- skull-structure? and his theories are linked to some dodgy 'white race' page.. It should be clear that the existence of a specific genetic marker Haplogroup R1a1 (Y-DNA) does not necessarily relate to the appearance (skull-structure) or colour of skin of a person. Even though it is interesting to see how the genes distribution is consistent with the thus far lingustically theoretical Proto-Indo-Europeans But note that the article's links are considere pseudo-science and that this is a highly controversial field... As of 1999, most Physical Anthropologists disagreed that there are any physical existing 'races' that differentiate the human race.
Max Nemo 28/02/07
[edit] Text
Maybe this text (from Indo-Aryan migration article) can be merged here: There has been significant progress in genetic studies of the Indian caste populations in the last five years (as of 2006); this has implications for the Indo-Aryan migration/invasion theory. The studies could be broadly classified into pro-racial and pro-cultural.
The genetic studies are ongoing with conflicting results: those that support an infusion of genetic material {Bamshad et al.(2001), Spencer Wells, Journey of Man(2002), Basu et al. (2003), Cordaux et al.(2004)} (pro-racial) and those that don't {Kivisild et al.(2003), Sengupta et al.(2005), Sahoo et al.(2006)} (pro-cultural). A final picture will emerge after critical and comparative analyses of these studies.
The pro-racial construction studies maintain that there exists "Aryan" Y-lineages in Indian(especially upper caste) population. The age of these Y-lineages in India coincided with the putative Aryan invasion period in their studies.
The pro-cultural construction studies argue that the lineages identified with the "Aryan" are in fact more diverse in lower caste and tribal populations even though their frequency is lower. Their studies came to the conclusion that most of Indian Y-chromosomes date back to late pleistocene.
Interestingly, western Eurasian mtDNA haplogroup U2i in pro-racial Bamshad et al. study turned into Eastern Eurasian(mostly India specific) in pro-culture Kivisild et al. study.
However, there are still doubts exist over autosomal admixture analysis. It is also suggested that Indian marital traditions may have an impact on the calculation of age of Indian Y-haplogroups.
The genetic views on race differ in their classification of Dravidians. Most modern anthropologists, however, reject the genetic existence of race[1], like Richard Lewontin who states that "every human genome differs from every other", showing the impossibility of using genetics to define races. (Biology as Ideology, page 68).[2] According to population geneticist L.L. Cavalli-Sforza of Stanford, almost all Indians are genetically Caucasian,[3] but Lewontin rejects the label Caucasian.[4] Cavalli-Sforza found that Indians are about three times closer to West Europeans than to East Asians. Genetic anthropologist Stanley Marion Garn considers the entirety of the Indian Subcontinent to be a "race" genetically distinct from other populations.[5][6] Others, such as Lynn B. Jorde and Stephen P. Wooding, claim South Indians are genetic intermediaries between Europeans and East Asians.[7][8][9] Recent studies of the distribution of alleles on the Y chromosome[2][3], microsatellite DNA[4], and mitochondrial DNA[5] in India have cast overwhelmingly strong doubt upon any biological Dravidian "race" as distinct from non-Dravidians in the Indian subcontinent. This doubtfulness applies to both paternal and maternal descent; however, it does not preclude the possibility of distinctive South Indian ancestries associated with Dravidian languages.[10]
[edit] Possible error
From the mtDNA section:
Virtually all modern Central Asian MtDNA M lineages seem to belong to the Eastern Eurasian (Mongolian) rather than the Indian subtypes of haplogroup M, which indicates that no large-scale migration from the present Turkic-speaking populations of Central Asia to India (and vice versa) could have occurred (Kivisild 2000).
This might be clarified. Migrations were sometimes mostly comprised of males, esp if migrations of conquest, Therefore the lack of Turkic mtDNA does not necessarily mean there was n;t any substantial migration of Turkic men into India Hxseek (talk) 08:36, 20 January 2008 (UTC)
- this is correct. we cannot draw our own conclusions. we need to phrase this along the lines of "Kivisild (2000) conclude ..." provided the conclusion is in the paper. Otherwise remove. dab (𒁳) 09:18, 20 January 2008 (UTC)
[edit] Bunch of stuff
Transfering incoherent material from Indo-Aryan migration#Physical anthropology. Some of it seems to be in the article already; whether any sense can be made of the rest remains to be seen.
However (Kivisild 2003a; Kivisild 2003b) have revealed that a high frequency of haplogroup 3 (R1a1) occurs in about half of the male population of Northwestern India and is also frequent in Western Bengal. These results, together with the fact that haplogroup 3 is much less frequent in Iran and Anatolia than it is in India, indicates that haplogroup 3 found among high caste Telugus did not necessarily originate from Eastern Europeans. The high diversity of haplogroup 3 and 9 in India suggests that these haplogroups may have originated in India (Kivisild 2003a). Studies of Indian scholars showed the R1a lineage forms around 35–45% among all the castes in North Indian population (Namita Mukherjee et al. 2001) and the high frequency of R1a1 present in the indigenous Chenchu and Badaga tribes of South India making the association with the Brahmin caste more vague. However, a model involving population flow from Southern Asia into Central Asia during Paleolithic interglacial periods with a subsequent R1a1-mediated Neolithic migration of Indo-European-speaking pastoralists back into Southern Asia would also be consistent with these data. A further study (Saha et al 2005) examined R1a1 in South Indian tribals and Dravidian population groups more closely, and questioned the concept of its Indo-Iranian origin. Most recently Sengupta et al. (2006) have confirmed R1a's diverse presence including even Indian tribal and lower castes (the so-called untouchables) and populations not part of the caste system. From the diversity and distinctiveness of microsatellite Y-STR variation they conclude that there must have been an independent R1a1 population in India dating back to a much earlier expansion than the Indo-Aryan migration. The pattern of clustering does not support the model that the primary source of the R1a1-M17 chromosomes in India was a single entry of Indo-European speaking pastoralists from Central Asia. However, the data are not necessarily inconsistent with more complicated demographic scenarios involving multiple entries in both Paleolithic and Neolithic periods and two-way population flows into and out of South Asia. In addition, there remains a difference in haplogroup prevalence between present day Indo-Aryan and Dravidian speakers[citation needed] and between upper and lower castes. The preponderant haplogroup amongst a proportion of Indo-Aryan populations and upper castes is R (both R1a and R2) and, amongst tribal groups and lower castes, to a higher extent Dravidian ones, it is haplogroup H (Y-DNA). The high prevalence of haplogroup R1a (around 50-60%) combined with the relatively low prevalence of haplogroup H in the northwestern portion of the subcontinent (northwestern India and present-day Pakistan) also suggests an affinity between this part of the subcontinent and the Central Asian steppes, perhaps brought about by longstanding two-way population flows. The absence of haplogroup R1b (Y-DNA) in Indo-Aryan and Dravidian populations which is found in all other Indo-European populations, in especially large proportions in western Europe, may suggest significant levels of native genetic base for the Indo-Aryan peoples compared to other Indo-European peoples. However, it must be noted that R1b is also not present in significant levels in Slavic and Central Asian populations.
Bafflegab at its finest. rudra (talk) 07:19, 22 January 2008 (UTC)
[edit] Haplogroup L
There is a whole paragraph that looks as self-research (and obviously lacks of any sources):
Most of the pro-migration papers imply that R1a1 is the genetic marker that is representative of a migration, due to its high frequency in Eurasia. But an equally likely genetic marker is haplogroup L. This haplogroup is present in Greek, Turkish, Lebanese, Iranian, Central Asian, and Indian populations (and Europe, see Kivisild). This marker is found in locations where written sources record the presence of Indo-European languages and people: i.e. Greeks, Hittite, Mitanni, Iranians and Indians. Its peak frequency is found in Indo-Iranian populations. The 'Western Eurasian' components that are found in Indian mtDNA show a distribution closer to that found in the Southern Caucasus and Middle East than to that found in Eastern Europe. There is also the question of why one should assume only one Y haplogroup is representative of the Aryan gene pool. R1a1, R1b, J2, L and H - all of which are present in India and Central and West Asia - are all possibilities. However, haplogroup L has a very low level of diversity in the Punjab. This is suggestive of a recent migration or expansion event in the area, and is supported by the fact that the diversity of R1a1, J2 and haplogroup C is higher in the region. Haplogroup C is supposed to be the remmants of the "Out of Africa" migration of humans, but still retains a high level of diversity. Haplogroup L is also found in South India at relatively high freqencies and has been associated by some (along with J2) with the spread of farming and Dravidian languages. However haplogroup L1 is the dominant one in southern India, hence may represent an expansion event in the South (or elite dominance from the North).
Haplogroup L does exist in Western Asia (Iran, Turkey) [6][7], but it is quite rare. It doesn't seem to justify the hypothesis expressed above and in any case, it should not be self-research but the elaboration of an academic opinion.
H is not present (except maybe erratics and the well known case of the Roma people) outside of South Asia.
And I really don't understand why macrohaplogroup C (most common in NE Asia and Oceania) is even mentioned in that context, really.
Overall the paragraph looks a very good candidate for deletionist practices. --Sugaar (talk) 08:25, 10 March 2008 (UTC)
