Fig. 1: A map reconstructing human migration across Asia over the course of ancient history. The genetic data, which were paired with linguistic groupings, suggest that South Asia and Southeast Asia served as a starting point for subsequent population movement throughout the continent.
© 2010 The HUGO Pan-Asian SNP Consortium
Research collaborations rarely produce a political as well as scientific triumph. However, a recently completed, large-scale genetic mapping project from a diverse team of Asian scientists associated with the Human Genetics Organization (HUGO) has accomplished this feat.
“The primary goals of this project were to understand the relatedness and diversity of Asian populations; to plan, execute and publish a project that originated in Asia; and to start a process of Pan-Asian collaboration that has not existed before in our field,” says Edison Liu, executive director of the A*STAR Genome Institute of Singapore and one of the scientific leaders of the HUGO Pan-Asian SNP Consortium.
The objective was to exploit small sequence changes that have emerged in the human genome over the course of history—single nucleotide polymorphisms—to reconstruct a timeline of migration and thereby essentially track the bloodlines of the diverse ethnic groups that populate the various Asian nations.
The scientific effort alone was daunting—mapping 54,794 single nucleotide polymorphisms in nearly 2,000 individuals from 75 ethnic groups and 11 countries—but the challenge was amplified by the effort to ensure that every participant was an equal partner. Developing nations such as Indonesia and the Philippines brought valuable genetic diversity to the table, but were constrained by limited research infrastructure relative to more homogeneous nations such as Japan and Korea, necessitating creative solutions. “We developed a host–guest system,” says Liu. “Guests would be invited to physically bring their national DNA to host institutions to perform the genotyping…in this manner, less enabled countries could learn key technologies from host countries, but never relinquished sovereignty over their samples.”
The researchers uncovered evidence for a common ancestral origin for both East and Southeast Asian populations, and reconstructed the probable flow of human movement throughout the region over the course of many millennia (Fig. 1). “An earlier hypothesis suggested that Northern Asia was populated by two waves of migration: one from Southeast Asia and the second from the North,” says Liu. “Our data showed no evidence for a Northern contribution to Asia’s genetics; the genetic source for all of Asia appears to be from Southeast Asia.”
The Consortium is already looking to tackle more complex questions of genetic distribution and disease susceptibility by expanding the analysis to nearly a million sequence variations in a larger study group, but Liu feels the team is up to the challenge. “We have a strong network of collaborative scientists from across Asia,” he says.
The A*STAR-affiliated authors in this highlight are from the Genome Institute of Singapore.
