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S.S. PAPIHA1
Abstract In the last 25 years a number of genetic studies on the populations of the Indian subcontinent have been conducted. Unfortunately, most of the studies covered a limited number of genetic systems, and only a few provide information on the genetic differentiation and population structure of some regional caste, tribal, religious, and urban groups. Despite a recent report suggesting that in eastern India genetic affinity does not show any large degree of congruence with sociocultural hierarchy, three distinct surveys reported here indicate that geographic proximity, ethnohistory, and biosocial and cultural affiliation are important determinants of genetic affinity. Gene differentiation studies are few, but from the information of some previous papers and results presented in this special issue of Human Biology, the pattern of differentiation is becoming clear. In general, genetic differentiation in populations of India is low (0.261.7%), but overall genetic differentiation in 18 mixed populations of India is higher (2.23%), similar to the largest single study on 16 tribal groups from central India (2.18%). The tribal population of South India shows the highest FST value (4.1%), and this value is similar to a study of the Dhangar caste group. The reason for this high FsT value is not clear. One possibility may be (semi-) isolation associated with such factors as random inbreeding and drift, which can cause high levels of genetic differentiation among the tribal groups of India and among the castes such as Dhangar. However, further studies are needed to explore the causes of such high values of genetic differentiation, especially in these populations.
It was 27 years ago that the first multisystem biochemical genetic study on the population of South India was reported (Ananthakrishnan and Kirk 1969). Soon after, D.F. Roberts and colleagues started work on genetic variation among the Sinhalese population of Ceylon, now known as Sri Lanka (Roberts et al. 1972). Since then, knowledge of multisystem genetic variation among the populations of the Indian subcontinent has been steadily increasing, especially because of the work of several local scientists and the activities of three main overseas laboratories, two in Europe (Newcastle, England, and Bremen, Germany) and one in Australia (Canberra). During this period, enormous advances in the analysis of such genetic variation have also been made. New biochemical...