Submitted to: Mammalian Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 16, 1999
Publication Date: November 1, 1999
Citation: Grosse, W.M., Kappes, S.M., Laegreid, W.W., Keele, J.W., Chitko Mckown, C.G., Heaton, M.P. 1999. Single nucleotide polymorphism (SNP) discovery and linkage mapping of bovine cytokine genes. Mammalian Genome. 10:1062-1069. Interpretive Summary: Cattle infected with foodborne pathogens are a human health issue as well as a significant source of economic loss to the cattle industry. The focus of this study was to identify markers for bovine genes that may influence infection resistance. Thirty-one genetic markers were identified in seven immune function genes. These markers, single nucleotide polymorphisms, are esuitable for use in DNA chip technologies that measure genetic variation. Genetic variation associated with these genes may help identify livestock that are resistant to infection by foodborne pathogens.
Technical Abstract: Polymorphic markers at bovine gene loci facilitate the integration of cattle genetic maps with those in humans and mice. To this end, 31 single nucleotide polymorphism (SNP) markers were developed for 7 bovine chemokine genes. Loci were amplified from bovine genomic DNA by the polymerase chain reaction and candidate amplicons were sequenced to determine their identity. Amplified loci from 24 founding parents of a beef cattle reference population were sequenced and analyzed for SNPs. SNP haplotype alleles were determined by examining segregation patterns in progeny and used to establish the locus position on the bovine linkage map. Loci for growth-related proteins (GRO3, GRO1, and GROX) were clustered with the related CXC chemokine genes, interleukin (IL) 8 and epithelial cell inflammatory protein 1, at 84 cM from the centromeric end of the bovine chromosome (BTA) 6 linkage group. Bovine loci for a cluster of IL8 receptors, a stromal cell-derived factor 1, interferon-gamma, and tumor necrosis factor-alpha were mapped at 90, 55, 59, and 34 cM, respectively, from the centromeric ends of the BTA 2, 28, 5, and 23 linkage groups. The positions of these bovine loci were compared with those of orthologous loci on the human map to refine the boundaries of conserved synteny. These 7 loci provide examples of SNP development in which the efficiency was largely dependent on the availability of bovine genomic or cDNA sequence. The polymorphic nature of the SNP haplotype markers suggests that they will be useful for evaluating whether variation in these genomic regions influences resistance to infectious disease.