The origin of the domestic pig: Independent domestication and subsequent introgression

The domestic pig originates from the Eurasian aid boar (Sus scrofa). We hav e sequenced mitochondrial DNA and nuclear genes from wild and domestic pigs from Asia and Europe. Clear evidence was obtained for domestication to hav e occurred independently from wild boar subspecies in Europe and Asia. The time since divergence of the ancestral forms was estimated at similar to 50 0,000 years, well before domestication similar to 9,000 years ago. Historic al records indicate that Asian pigs were introduced into Europe during the 18th and early 19th centuries. We found molecular evidence for this introgr ession and the data indicated a hybrid origin of some major "European" pig breeds. The study is an advance in pig genetics and has important implicati ons for the maintenance and utilization of genetic diversity in this livest ock species.