By KEVIN WALKER
EDINBURGH — T.J. Tabasco may not be the most famous pig in the world today, but she sure is important.
In 2002 scientists from the University of Illinois took a piece of skin from T.J.’s ear and, from it, generated a fibroblast cell line. This ultimately led to the draft pig genome, which was published in the Nov. 15 issue of Nature. The development has implications for both agriculture and medical research.
“Agriculture in particular will benefit fast,” said Alan Archibald of the Roslin Institute in Edinburgh, Scotland, in an article accompanying the research report; he is one of the paper’s lead authors. “The pig industry has an excellent track record for rapid adoption of new technologies and knowledge.”
Jim Ireland, a professor in the Department of Animal Science at Michigan State University and an expert on animal research issues, said the pig genome will lead to new genomic and diagnostic methods to improve the value of livestock pigs.
Because of the genome, advances in selection and breeding techniques will be much faster than would be the case otherwise. This will enhance the “genetic merit” of farm animals compared with traditional animal breeding practices, he stated.
“Producers can expect this new information to lead to farm animals with superior health, fertility and herd longevity,” Ireland explained.
These advances should, in turn, lead to reduced antibiotic use, as well as improvements in the growth, quantity and quality of milk, meat and eggs. In the end it should lead to a reduction in the use of stimulants, as well. For their part, consumers can expect high-quality animal products produced in the United States to remain abundant and relatively affordable, Ireland added.
In the research report the authors, which number more than 100, explain they have been able to acquire a better understanding of how pigs evolved, how domestic and wild pigs mixed together at different points in history and how Asian and European pigs mixed at different times.
The genome and associated research will help scientists exploit the similarities between pig and human physiologies. The pig is an important biomedical model.
In a podcast made available along with the article, geneticist and co-author Martin Groenen of Wageningen University in the Netherlands provided his own insights into the development.
“Of course, it’s a very important animal for agricultural use, and there’s still a lot of improvements in breeding going on. Another important aspect of the pig is that it’s also a biomedical model because of the similarity in physiology to humans,” he said.
He said pigs are important because they can eat many foods humans can’t, which are considered waste products. As such, he said pigs turn what would otherwise be thrown away into a high-quality protein humans can consume.
Groenen noted the researchers have made genome sequences of other hogs as part of this research, including 10 wild boars. The scientists discovered a million genetic base pair positions that are different between Chinese wild boars and European wild boars. He noted that wild boars separated from domestic pigs about a million years ago.
Through the research they were able to discover Chinese domestic pigs are much closer to Chinese wild boars and European domestic pigs are much closer to European wild boars.
“It’s clear that they really formed two different groups,” Groenen explained.
But he said it was in the 18th and 19th centuries that breeders in the West began importing Chinese pigs to develop traits they thought were desirable. Therefore, today domestic pigs in the West possess much genetic material obtained from Chinese pigs.
Regarding biomedical research, Groenen said pigs possess a number of variants that also occur in humans, which are disease-related. He said these variants might not be important for pigs, but they sometimes are important for humans, including diseases that occur late in life, such as cancer.
He said pigs are also important medically since they have organs that are similar in size to humans. He explained the pig genome can help identify viruses that aren’t active in pigs but that could become active in humans once a pig organ is transplanted to a human. The knowledge this genome provides may help scientists develop pigs that are safer to use for transplantation purposes.