As per a recent comment this thread is meant to voice contrarian opinions, that is anything this community tends not to agree with. Thus I ask you to post your contrarian views and upvote anything you do not agree with based on personal beliefs. Spam and trolling still needs to be downvoted.
a) Actually Thapar's point wasn't that there were no genetic differences (in fact, the theory of caste promulgated by Dalit activists is that it's created by the prohibition of inter-caste marriage and therefore pretty much predicts genetic differences) - but that the groupings done by the researchers wasn't the correct one.
b) I should actually check that what I surmised is what she said. Thanks for alerting me to the possibility.
So do you have independent evidence that the theory promulgated by the Dalit activists is correct, because theories promulgated by activists don't exactly have the best track record.