What is in this article?:
- Pig genome offers window into human health
- Shedding pig light
- Genomic analysis reveals unexpected and potentially beneficial similarities between pigs and humans.
- New analysis helps understand the genetic mechanisms that enable high-quality pork production, feed efficiency and resistance to disease.
The pig and its cousin the wild boar have much in common with humans. They are world travelers. They’re adaptable, invasive and often damage their own habitat. They are easy to seduce (with food) and susceptible to domestication, but when conditions allow, they revert to a feral lifestyle.
A new genomic analysis reveals some new, unexpected and potentially beneficial similarities between pigs and humans, along with a few distinct differences. The International Swine Genome Sequencing Consortium – led by researchers at the University of Illinois, Wageningen University in the Netherlands and the University of Edinburgh – conducted the analysis. Theirs is the most thorough genomic study yet conducted of the domestic pig and its wild boar counterparts.
A report of the study appears as the cover article in the November 15, 2012, issue of the journal Nature.
“It is exciting that the genomic sequence of the domestic pig now is in the public domain and available to enable more powerful approaches to domestic swine and pork improvement,” said Ronnie Green, University of Nebraska Vice Chancellor for the Institute of Agriculture and Natural Resources and an early supporter of the pig genome sequencing project at the U.S. Department of Agriculture. “It will also aid efforts to use the pig as a model for biomedical research and the improvement of human health.”
“This new analysis helps us understand the genetic mechanisms that enable high-quality pork production, feed efficiency and resistance to disease,” said Sonny Ramaswany, the director of the U.S. Department of Agriculture’s National Institute of Food and Agriculture. “This knowledge can ultimately help producers breed high-quality swine, lower production costs and improve sustainability.”
The researchers compared the genome of a common farm pig, Sus scrofa domesticus, with those of 10 wild boars – all from different parts of Europe and Asia. They also compared the pig genome with the human, mouse, dog, horse and cow genomes.
The team discovered new details of Sus scrofa evolution after the ancestors of the domestic pig, which most resembled today’s wild boars, first emerged in Southeast Asia and gradually migrated across Eurasia.
Comparisons of Asian and European wild boars revealed significant genetic differences, the result of their separating from one another roughly 1 million years ago, said University of Illinois Vice President for Research Lawrence Schook, a principal investigator on the study.
“They have been separated so long that the Asian and European lineages are almost sub-species now,” Schook said. The European and Asian wild boars lost a lot of genetic diversity about 20,000 years ago, likely as a result of a global glaciation event.
Comparisons of domestic and wild pigs also “revealed a clear distinction between European and Asian breeds,” the researchers wrote. This adds to the evidence that “pigs were independently domesticated in western Eurasia and East Asia.”
“We had evidence from previous studies, but those studies focused on the mitochondrial DNA, a small DNA molecule only inherited from the mother,” said Wageningen University professor Martien Groenen, also a principal investigator on the study. “With the complete genome sequence of multiple wild boars we now have a much clearer picture about these events.”