Deciphering the West Eurasian Genetic Footprints in Ancient South India

Since 2006, Pattanam coastal village of the Ernakulam District in Kerala, India, has witnessed multi-disciplinary archaeological investigations in collaboration with leading research institutions across the world. The results confirm that the Pattanam site could be an integral part of the lost ancient port of Muziris, which, as per the material evidence from Pattanam and its contemporary sites, played an important role in the transoceanic exchanges between 100 BCE (Before Common Era) and 300 CE (Common Era). So far, the material evidence with direct provenance to the maritime exchanges related to ancient cultures of the Mediterranean, West Asian, Red Sea, African, and Asian regions have been identified at Pattanam. However, the genetic evidence supporting the impact of multiple cultures or their admixing is still missing for this important archaeological site of South India. Hence, in the current study, we tried to infer the genetic composition of the skeletal remains excavated from the site in a broader context of South Asian and worldwide maternal affinity. We applied the MassArray-based genotyping approach of mitochondrial makers and observed that ancient samples of Pattanam represent a mixed maternal ancestry pattern of both the West Eurasian ancestry and the South Asian ancestry. We observed a high frequency of West Eurasian haplogroups (T, JT, and HV) and South Asian-specific mitochondrial haplogroups (M2a, M3a, R5, and M6). The findings are consistent with the previously published and ongoing archaeological excavations, in which material remains from over three dozen of sites across the Indian Ocean, Red Sea, and Mediterranean littoral regions have been unearthed. This study confirms that people belonging to multiple cultural and linguistic backgrounds have migrated, probably settled, and eventually died on the South-western coast of India.