TY - JOUR T1 - The genetic legacy of Zoroastrianism in Iran and India: Insights into population structure, gene flow and selection JF - bioRxiv DO - 10.1101/128272 SP - 128272 AU - Saioa López AU - Mark G. Thomas AU - Lucy van Dorp AU - Naser Ansari-Pour AU - Sarah Stewart AU - Abigail L. Jones AU - Erik Jelinek AU - Lounès Chikhi AU - Tudor Parfitt AU - Neil Bradman AU - Michael E. Weale AU - Garrett Hellenthal Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/04/20/128272.abstract N2 - Zoroastrianism is one of the oldest extant religions in the world, originating in Persia (present-day Iran) during the second millennium BCE. Historical records indicate that migrants from Persia brought Zoroastrianism to India, but there is debate over the timing of these migrations. Here we present novel genome-wide autosomal, Y-chromosome and mitochondrial data from Iranian and Indian Zoroastrians and neighbouring modern-day Indian and Iranian populations to conduct the first genome-wide genetic analysis in these groups. Using powerful haplotype-based techniques, we show that Zoroastrians in Iran and India show increased genetic homogeneity relative to other sampled groups in their respective countries, consistent with their current practices of endogamy. Despite this, we show that Indian Zoroastrians (Parsis) intermixed with local groups sometime after their arrival in India, dating this mixture to 690-1390 CE and providing strong evidence that the migrating group was largely comprised of Zoroastrian males. By exploiting the rich information in DNA from ancient human remains, we also highlight admixture in the ancestors of Iranian Zoroastrians dated to 570 BCE-746 CE, older than admixture seen in any other sampled Iranian group, consistent with a long-standing isolation of Zoroastrians from outside groups. Finally, we report genomic regions showing signatures of positive selection in present-day Zoroastrians that might correlate to the prevalence of particular diseases amongst these communities. ER -