SHEEP breeders will soon have the ability to use DNA "fingerprinting" to accurately identify the pedigree of individual lambs and improve the genetic performance of their flock. The CSIRO division of animal production in collaboration with Macquarie University have developed a prototype parentage testing system for Merino sheep based on DNA markers. This system enables sheep breeders to establish both the paternity and maternity of their lambs with an error rate of less than 0.1 per cent. While the technology has been available for a while, in the past it has been too expensive to be used commercially. But the new system, profiled at the CSIRO's Yalanbee research station field day at Bakers Hill earlier this year, should prove more accessible at about $20 a test. By knowing the pedigree of a lamb, sheep breeders can more accurately assess the performance of a ram's progeny and determine its breeding value. It also provides information to identify undesirable genes, such as dark pigment, so the animals can be easily identified and eliminated. The system can also be used to remove the undesirable effects of inbreeding. CSIRO communications manager Pat Wilson said, when combined with a breed evaluation assessment, such as the Unbiased Linear Predication system known as BLUP, the rate of genetic progress could be increased by up to 25 per cent. Ms Wilson said a veterinarian would not be required to do the DNA tests. Producers could take the blood samples from the sheep themselves and send it off to a laboratory for testing. Eventually, DNA testing would become more useful as more genetic markers were found to identify performance characteristics of individual animals such as fibre diameter and clean fleece weight. Work is already underway at the CSIRO's Sydney laboratory to distinguish these markers from more than 14,000 gene sequence tags.