Back on the farm, early knowledge about the pig genome led to the discovery in 1991 of a gene involved in porcine stress syndrome, in which the stress of overheating, being moved or even having sex causes the animals to die suddenly. It then became possible to test for the gene and select pig stocks free of it.
Having the full genome should also help investigators to breed out susceptibility to porcine reproductive and respiratory syndrome (PRRS), a viral disease costing the US pig industry US$600 million per year. The PRRS Host Genetics Consortium, a network of US research groups, has identified a region on one chromosome that affects levels of virus in the blood during infection. Archibald, who works on PRRS, says that the high-quality genome sequence should help investigators zero in on the genes responsible.
But the pig genome is not just about applications. Lead co-author Martien Groenen, a genome researcher from Wageningen University in the Netherlands, has resequenced the genomes of scores of different strains of wild and domestic pigs, and used the information to show that the pig was domesticated independently in Asia and Europe. He has also started to work out which genes were involved in the selection of desired traits — such as a longer spine to give more bacon — on different continents. “It’s curiosity-driven research, but it may also help animal breeders in the future,” he says.