Submitted to: Proceedings of the National Academy of Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 26, 1996
Publication Date: N/A
Interpretive Summary: Bovine chromosome specific libraries were made for the long and short arm of the X chromosome. The two libraries were shown to be X chromosome-specific and were used to demonstrate the homologous regions of the sheep and goat X chromosomes. Ten informative markers were developed from the long arm library and were used to generate a linkage group for the long arm of the bovine X chromosome. The linkage group contains 15 markers and covers 89 cM. This approach demonstrates the usefulness of chromosome specific libraries for developing additional markers for specific regions of the genome.
Bovine chromosome short arm (Xp) and long arm (Xq) painting probes and specific DNA libraries were prepared by chromosome micromanipulation, DNA micropurification, microcloning and PCR amplification. Chromosome specificity and segment homologies between the submetacentric bovine X chromosome and the acrocentric sheep and goat X chromosomes were assessed by fluorescent in situ hybridization. The bovine Xp chromosome painting probe identified an interstitially located homologous segment in the sheep and goat Xq. Primary microsatellite screening of the bovine Xq chromosome-specific DNA library yielded 3.7% positive clones. After the secondary, high stringency, screening and sequencing of positive clones, 32.8% were identified as unique clones. The microsatellite markers obtained from the Xq library and five other X-chromosome assigned but unlinked markers were used to generate a linkage map for Xq spanning 89.4 cM. We conclude that the generation of chromosome specific libraries from PCR amplified chromosomes is a useful source of genetic markers for livestock.