Scientists at the Genome Institute of Singapore (GIS) have made public the first genetic historical map of the Han Chinese, which may help in tracing disease susceptibility genes.
Based on genome-wide DNA variation information in over 6,000 Han Chinese samples from 10 provinces in China, this new map provides information about the population structure and evolutionary history of this group of people that can help scientists to identify subtle differences in the genetic diversity of Asian populations.
Understanding these differences may aid in the design and interpretation of studies to identify genes that confer susceptibility to such common diseases as diabetes in ethnic Chinese individuals.
Understanding these differences also is crucial in exploring how genes and environment interact to cause diseases.
With the genetic map, the GIS scientists were able to show that the northern inhabitants of China were genetically distinguishable from those in the south, a finding that seems very consistent with the Han Chinese's historical migration pattern.
The genetic map also revealed that the genetic divergence was closely correlated with the geographic map of China.
This finding suggests the persistence of local co-ancestry in the country.
"The genome-wide genetic variation study is a powerful tool which may be used to infer a person's ancestral origin and to study population relationships," said Liu Jianjun, GIS Human Genetics Group Leader.
"By investigating the genome-wide DNA variation, we can determine whether an anonymous person is a Chinese, what the ancestral origin of this person in China may be, and sometimes which dialect group of the Han Chinese this person may belong to," Dr. Liu said.
"More importantly, our study provides information for a better design of genetic studies in the search for genes that confer susceptibility to various diseases," he added.
According to GIS Executive Director Edison Liu, "Dr. Liu has reconstructed a genetic historical map of the Chinese people as they migrated from south to north over evolutionary time."