Genetic study reveals some Aetas and Indians share ancient ancestry

Written by Kim Luces
Published Online GMA News

A genetic link between Indians and two Aeta populations were unveiled in a study whose proponents include Frederick Delfin, university research associate at the DNA Analysis Laboratory in the University of the Philippines, Diliman.

According to Delfin, it is commonly accepted that the Asia-Pacific—including the Philippines—was peopled by human migration that passed through the coast of South Asia. 

But the mitochondrial DNA (mtDNA) Indian-Philippine genetic link that Delfin and his team found “can be a signal of shared ancestry that actually originated from India”.

Two mtDNA sets, M52'58 and M52a, that both originate from Indian populations were found in the Aetas of Zambales and the Agtas of Iriga in the Philippines.

These shared common haplogroups show a link between the populations of India and the Philippines that is about 5,000 to 20,000 years old. This suggests that these migratory groups from India arrived before the Austronesian people landed in Philippine shores and populated the prehistoric Philippine archipelago.

Link found in female lineage

Mitochondrial DNA or mtDNA are the parts of a person's genome passed on by mothers to their children; only women pass them from generation to generation.

Common mtDNA haplogroups or specific lineages were found in some Philippine and Indian populations which suggest common origins between the two.

Since mtDNA ancestry is matrilineal and not a combination of genetic material from both parents, tracing someone's lineage through the mtDNA is a somewhat straightforward process.

Indian origins not found in other Southeast Asian groups

This connection, science blogger Nathaniel Hermosa said, is noteworthy because it is unique to the Philippines.

Established genetic studies showed that no such link has been found in other Southeast Asian groups. 

“We also studied about 1,700 other mtDNA genomes (samples or individuals) across the Asia-Pacific region and did not find these two haplogroups anywhere else,” Delfin said in an email interview with GMA News Online.