Competitive Exams: Genetic Analysis of Caste System
There have been several studies examining caste members as discrete populations, examining the hypothesis that their ancestors have different origins. A 2002 − 03 study by T. Kivisild et al. Concluded that the “Indian tribal and caste populations derive largely from the same genetic heritage of Pleistocene southern and western Asians and have received limited gene flow from external regions since the Holocene.” Studies point to the various Indian caste groups having similar genetic origins and having negligible genetic input from outside south Asia. However, a 2001 genetic study, led by Michael Bamshad of the University of Utah, found that the affinity of Indians to Europeans is proportionate to caste rank, the upper castes being most similar to Europeans. The researchers believe that the Indo-Aryans entered India from the Northwest and may have established a caste system, in which they placed themselves primarily in higher castes." Because the Indian samples for this study were taken from a single geographical area, it remains to be investigated whether its findings can be safely generalized.
An earlier 1995 study by Joanna L. Mountain et al. Of Stanford University had concluded that there was “no clear separation into three genetically distinct groups along caste lines” although “an inferred tree revealed some clustering according to caste affiliation” A 2006 study by Ismail Thanseem et al. Of Centre for Cellular and Molecular Biology (India) concluded that the “lower caste groups might have originated with the hierarchical divisions that arose within the tribal groups with the spread of Neolithic agriculturalists, much earlier than the arrival of Aryan speakers” and “the Indo-Europeans established themselves as upper castes among this already developed caste-like class structure within the tribes.” The study indicated that the Indian caste system may have its roots much before the arrival of the Indo-Aryans; a rudimentary version of the caste system may have emerged with the shift towards cultivation and settlements, and the divisions may have become more well-defined and intensified with the arrival of Indo-Aryans.
A 2006 genetic study by the National Institute of Biologicals in India, testing a sample of men from 32 tribal and 45 caste groups, concluded that the Indians have acquired very few genes from Indo-European speakers. More recent studies have also debunked the British claims that so-called “Aryans” and “Dravidians” have a “racial divide” A study conducted by the Centre for Cellular and Molecular Biology in 2009 (in collaboration with Harvard Medical School, Harvard School of Public Health and the Broad Institute of Harvard and MIT) analyzed half a million genetic markers across the genomes of 132 individuals from 25 ethnic groups from 13 states in India across multiple caste groups. The study establishes, based on the impossibility of identifying any genetic indicators across caste lines, that castes in South Asia grew out of traditional tribal organizations during the formation of Indian society, and was not the product of any “Aryan Invasion” and “subjugation” of Dravidian people.