Will we ever eat pigs genetically engineered to give us healthy fats?

Mar 26 2006

Researchers in the U.S. have created pigs that produce omega-3 fatty acids, which are believed to improve heart function and help reduce the risks for heart disease.

The pigs represent the first cloned, transgenic livestock in the world that can make the beneficial compound.

The scientists genetically engineered the pigs to make beneficial omega-3 fatty acids and say they could ultimately offer a healthier source of pork chops or bacon.

Currently, the only way for humans to realize the benefits of omega-3 fatty acids is by taking dietary supplements or by eating certain types of fish that also contain high levels of mercury.

The team led by Yifan Dai of the University of Pittsburgh School of Medicine included researchers from the University of Missouri-Columbia National Swine Resource and Research Center, Massachusetts General Hospital (MGH), and the University of Pittsburgh.

Dai an associate professor of surgery at the University of Pittsburgh School of Medicine, says that while fish is one of the best food sources of omega-3 fatty acids, high mercury levels means consumption must be limited.

Dai says these animals could represent an alternative source as well as be an ideal model for studying cardiovascular disease and autoimmune disorders.

According to co-author Randy Prather, a professor of reproductive biology in Mizzou’s College of Agriculture, Food and Natural Resources, pigs and humans have a similar physiology and they were able to use the animals as a model to see what happens to heart health if omega-3 levels in the body were increased.

In their search for another source of omega-3s, the researchers transferred a worm gene called fat-1 into pig cells in a laboratory and then used cloning technology to create embryonic cells that were implanted into the womb of a normal pig.

The researchers say the gene produced an enzyme that converted the less desirable omega-6 fatty acids that the pigs naturally produced into omega-3s.

It seems tissue from the piglets that were born at the University of Missouri-Columbia had high levels of omega-3s and less omega-6, while the total amount of fat was the same as in normal pigs.

It is thought that too much omega-6 is a major factor in high rates of obesity and heart disease, and experts encourage higher consumption of omega-3.

Although pregnant women are advised that omega-3s are important for fetal development they are also warned to limit consumption of fish that may be high in mercury, which can be harmful to the fetus.

Controversy over any food which has been genetically engineered and the public lack of confidence in scientifically altered animals however makes the future for such products uncertain.

The findings are published in the April 6 issue of Nature Biotechnology.