KEY POINTS:
Townies still won't know the difference but New Zealand scientists have found a way to map the genetic code of the average sheep.
AgResearch has completed work on an international project mapping the sheep genome which will allow it to start identifying markers for valuable traits in yield, quality and disease-resistance.
"It's a step on the way to creating tools that will allow sheep breeders to select animals based on DNA markers that can indicate useful traits," said the state science company's senior scientist, John McEwan.
"Historically, farmers have had to record the pedigree and production traits of livestock to ascertain their value.
"The tools we are helping develop will enable them to determine this faster and more accurately."
AgResearch is one of 19 organisations from Australia, New Zealand, the United States, Britain, France and Kenya that make up the International Sheep Genomics Consortium (ISGC) developing public "maps" which will help researchers find genes associated with such traits.
The sheep genome data will allow scientists based at the AgResearch campus, at Mosgiel near Dunedin, to leverage knowledge they have been accumulating on the genetics involved in money-making traits such as fecundity, resistance to parasites and diseases such as foot-rot, wool weight and growth rates, and muscle sizing.
It will be used to identify single nucleotide polymorphisms (SNPs), the small genetic differences that mark out a particularly productive or disease-resistant animal from the rest of the flock.
The scientist will now create, by July, an SNP "chip" to scan the genome for 60,000 variants in a single pass, rather than having to conduct separate tests for each variant.
These glass chips will have pieces of DNA chemically bonded to them to pick out the specific nucleotide sequences being sought, and can be read quickly by a computer.
The consortium has been formally working on the broad project since 2002, and in 2006 created a map of 98 per cent of the sheep genome compiled with the aid of data from cows, dogs and humans.
This used genetic material from 10 individuals from two species of wild sheep, plus a collection of 308 animals from 19 domestic breeds drawn from Africa, Europe, North America, Asia, Australia and this country.
The project to create a sheep SNP chip should be completed by July, in time for ram breeders to benefit in next year's breeding season.
- NZPA
