We frequently hear that eating fish is a healthy thing to do, because it's full of beneficial long chain fatty acids. Unfortunately, the Western diet tends to be short on fish and bigger on beef, which contains short chain fatty acids that aren't quite so good for us. Chinese scientists are creating a work-around, however – genetically-engineered beef that's high in the "good" fatty acids.

Fish is a prime source of long chain n-3 polyunsaturated fatty acids, more commonly known as omega-3 oils, which help protect against obesity, cardiovascular disease and neurodegenerative disorders. The short chain fatty acids in beef are known as n-6.

In order to turn n-6 into n-3, a research team from China's Northwest A and F University, and National Beef Cattle Improvement Centre, first isolated the fat1 gene from a nematode worm. That gene codes for desaturase enzymes, which play a key role in converting n-6 fatty acids to n-3.

The scientists then introduced that gene into fetal cells from Luxi Yellow cattle, which are known for having a high beef yield. This resulted in calves being born with meat containing over five times more omega-3 oils than that of ordinary cows. Unfortunately 11 of the 14 calves died at an age of less than four months, due mainly to inflammation and haemorrhagic septicaemia, which is an infection common to cattle – so more work still needs to be done.

"There is much to learn about the best scientific techniques and the best husbandry required to make beef a rich animal source of omega-3 oils for human nutrition, but we have taken the first step," says Gong Cheng, lead author of a paper on the research.

In the meantime, other groups are looking at achieving the same ends by producing cattle feed that's rich in n-3 fatty acids, and by introducing genes similar to fat1 to sheep, pigs and dairy cattle – in the case of the latter, to produce milk that's high in omega-3 oils.

The research paper was recently published in the journal Biotechnology Letters.