A GENETIC-LINKAGE MAP OF THE BOVINE GENOME

A cattle genetic linkage map was constructed which marks about 90% of the expected length of the cattle genome. Over 200 DNA polymorphisms w ere genotyped in cattle families which comprise 295 individuals in ful l sibling pedigrees. One hundred and seventy-one loci were found linke d to one-other locus. Twenty nine of the 30 chromosome pairs are repre sented by at least one of the 36 linkage groups. Less than a 50 cM dif ference was found in the male and female genetic maps. The conserved l oci on this map show as many differences in gene order compared to hum ans as is found between humans and mice. The conservation is consisten t with the patterns of karyotypic evolution found in the rodents, prim ates and artiodactyls. This map will be important for localizing quant itative trait loci and provides a basis for further mapping.