(2018), steppe pastoralists are a likely source for R1a in India.According to other scholars, R1a1a steppe gene has been attributed to later Indo-Scythian and other central asian invasions.This theory is substantiated by the high prevelence of Swat valley Pashtun genetic markers among certain Indian castes like the Jats, Aroras, Sainis, Shakyas and Mauryas.