A map of the bovine genome will be an important tool for identifying genes causing congenital defects, and those controlling disease susceptibility and production traits in both beef and dairy cattle. Over 300 genes have already been mapped and a low resolution map should be available within two years. We are actively involved in the EC funded European Bovine Genome Mapping Group. To date our work has involved the development of markers and studies of experimental designs, two necessary precursors of a large scale bovine genome mapping project. In this article we briefly describe ongoing projects underpinning and improving the prospects for mapping bovine genes affecting disease and production.

For a linkage map of the bovine genome to be of use, the markers should display high levels of polymorphism. The most common markers on the map of the human genome are restriction fragment length polymorphisms (RFLPs), however these are usually diallelic, often with one allele at high frequency. We have been concentrating our efforts on the production of a relatively new class of marker, the micro-satellite.