Sheep Fertility Breakthrough to Have Human Implications

Article excerpt

Byline: RICHARD HALLORAN

A NEW breakthrough on sheep fertility by scientists at the Teagasc research centre at Athenry, Co Galway, could have major significance for research on control of fertility in women.

A team of researchers, led by Dr Seamus Hanrahan, of Teagasc Athenry, has identified three new gene mutations which have a profound effect on ovarian function.

As well as having significant potential benefits for sheep production, Dr Hanrahan told Farming Life that the discovery is likely to provide important insights for human fertility.

Using DNA technology, the scientists have found two distinct genes with a large effect on ovulation rate in sheep.

Two different mutations have been found in one of these genes.

"One of the genes is on the X-chromosome and, therefore, males can only inherit it from their mother. In the case of the second gene, individuals can inherit it from either parent.

"We are the first group of researchers in the world to have discovered that this second gene affects ovulation rate in sheep,'' said Dr Hanrahan.

"Ewes that inherit a single copy of any of the three mutations have a significantly higher ovulation rate. The effect could be an increase in litter size of between 0.5 and one lamb per ewe.

"Only improvements at the lower end of the scale would be practical under Irish sheep production conditions,'' he said. …