Author
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Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/2/2004 Publication Date: 8/1/2004 Citation: Nonneman, D.J., Rohrer, G.A. 2004. Comparative mapping of human chromosome 10 to pig chromosomes 10 and 14. Animal Genetics 35:338-343. Interpretive Summary: Sufficient variation in production traits exists in commercial populations of livestock to exploit allelic variation of superior animals to increase production efficiency and improve the quality of livestock products. Constructing detailed comparative maps with human and mouse genomes can help identify predictive markers in chromosomal regions that impact production traits in swine. Current comparative maps suggest that large genomic blocks are conserved between pig and human, while gene order for many regions is quite divergent. High-resolution comparative maps in chromosomal regions affecting traits of interest allow the development of additional nearby markers and selection of positional candidate genes that may cause phenotypic differences. The objective of this study was to construct a systematic ordered comparative map of human chromosome 10 that corresponds to pig chromosomes 10 and 14. Several economically important traits have been discovered on both pig chromosomes. Since a large portion of both pig chromosomes are represented by human chromosome 10, genes at regularly spaced intervals along this chromosome were targeted for placement on the maps. Thirty markers were developed and the locations of twenty-eight genes were assigned on the linkage and radiation hybrid maps. Comparative maps of mammalian species indicate that genes in chromosomal segments are conserved across several species and tend to be contained in blocks with distinct breakpoints. The addition of these genetic markers to the comparative maps provides sufficient density for the selection of positional candidate genes that could affect variation in quantitative traits. Technical Abstract: Identification of predictive markers in QTL regions that impact production traits in commercial populations of swine is dependent in construction of dense comparative maps with human and mouse genomes. Comparative mapping in swine suggest that large genomic blocks are conserved between pig and human, while mapping of individual genes reveals that gene order can be quite divergent. High-resolution comparative maps in regions affecting traits of interest are necessary for selection of positional candidate genes to evaluate nucleotide variation causing phenotypic differences. Although high-density physical and linkage maps exist in the pig, gene order for most regions is poorly defined. The objective of this study was to construct a systematic ordered comparative map of human chromosome 10 and pig chromosomes 10 and 14. Several economically important traits have been discovered on both pig chromosomes. Since a large portion of both pig chromosomes are represented by HSA10, genes at regularly spaced intervals along this chromosome were targeted for placement in the porcine genome. A total of 28 genes from human chromosome 10 were mapped to porcine chromosomes 10 (SSC10) and 14 (SSC14) averaging about 5 Mb distance of human DNA per marker. Sixteen genes were assigned by linkage in the MARC mapping population, 5 genes were physically assigned with the IMpRH mapping panel and 7 genes were assigned on both maps. Sixteen genes from human 10p mapped to SSC10, and 12 genes from human 10q mapped to SSC14. Comparative maps of mammalian species indicate that chromosomal segments are conserved across several species and represent syntenic blocks with distinct breakpoints. Development of comparative maps containing several species should reveal conserved syntenic blocks that will allow us to better define QTL regions in livestock. |
