New discoveries about pig evolution in East Asia (11/27/2007)

The research into the origins of domestic animals is of significance not only for understanding their development per se, but also for understanding the human society evolution. Although there are evidences to show that pigs were independently domesticated in multiple places throughout the world, the detailed scenario of the origin and dispersal of domestic pigs in East Asia remains unclear.

Recently, a research team headed by Prof. ZHANG Yaping with the State Key Laboratory for Genetic Resources and Evolution, the CAS Kunming Institute of Zoology, has conducted mitochondrial population genomic analysis of domestic pigs and wild boars. Their work, which was published in the Nov. 19 issue of Genome Biology, shows that all domestic pigs in East Asia are clustered into a single clade D, and their domestication mainly occurred in the Mekong region and the middle and downstream region of the Yangtze River.

At present, the best available approach for the job is by means of population genomics. However, its sequencing costs are very high. To address the problem, the Kunming team and co-workers employed a novel strategy. They first obtained the primary phylogenetic information about domestic pigs and wild boars via analyzing the sequences of their mitochondrial DNA (mtDNA) control regions. Then the scientists constructed for the first time a phylogenetic tree of domestic pigs and wild boars in East Asia with wide-range representation on the basis of complete mtDNA sequences of individuals of different lineages. The results enabled the researchers to perform a fine-grained phylogeographic study of the Asian domestic pigs and wild boars and reappraise the published data. The use of fine-grained mtDNA phylogenomic analysis of wild boars and domestic pigs is a powerful tool to discern the origin of domestic pigs. This approach could also be used in elucidating the origin of other domestic animals such as chicken, cattle, sheep, and goats.

Note: This story has been adapted from a news release issued by the Chinese Academy of Sciences

Post Comments: