frequency of ca. 7-15% (Basu et al. 2003, Cordaux et al. 2004, Sengupta et al. 2006, Thamseem et al. 2006). It is especially frequent among Dravidian upper and middle castes (ca. 17-19%), but is somewhat rarer in Aryan upper and middle castes (ca. 5-6%), which suggests that it may have been