Development of microsatellite markers and comparative mapping for bovine chromosome 19

Previous research has mapped an ovulation rate quantitative trait locus (QTL) to bovine chromosome 19. In an effort to enhance comparative mapping information and develop additional markers for refined QTL mapping, microsatellite markers were developed in a targeted approach. A bovine bacterial artificial chromosome (BAC) library was screened for loci with either known or predicted locations on bovine chromosome 19. An average of 6.4 positive BAC were identified per screened locus. A total of 10 microsatellite markers were developed for five targeted loci with heterozygosity of 7-83% in a sample of reference family parents. The newly developed markers were typed on reference families along with four previously mapped marker loci and used to create a linkage map. Comparison of locus order between human and cattle provides support for previously observed rearrangement. One of the mapped loci myotubularin related protein 4 (MTMR4) potentially extends the proximal boundary of a conserved linkage group.