Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/30/1998
Publication Date: N/A
Technical Abstract: Identifying and mapping genes that influence infectious disease resistance in cattle is facilitated by the ability to adequately increase both marker density and the number of animals genotyped. Recent technological advances in molecular genetics have provided new opportunities in both of these areas by the use of single nucleotide polymorphisms (SNPs) in combination with chip-based microarray genotyping systems. The goal of this work was to determine the apparent SNP frequency in cytokine and related genes in a reference population of beef cattle developed at the U.S. Meat Animal Research Center (MARC). Genomic DNA segments from 9 genes on 5 chromosomes were amplified from 23 reference parents for sequence analysis. A total of 5.2 kb of unique DNA from predominantly non-coding regions was analyzed in each of the MARC reference parents. Forty-three SNPs were identified in these parents and verified by linkage analysis. Our results indicated that ta heterozygous SNP occurs every 497 bp in a given MARC reference parent. With regard to the entire reference population, an SNP occurred every 121 bp of amplicon sequence. SNP haplotypes were also constructed across each amplicon locus (600 bp average) for each parent and verified in progeny. An average of 4.8 haplotype alleles was observed per locus, and 36% of the reference parents had heterozygous alleles at each locus. Taken together, these results suggest that the frequency of cattle SNP markers is adequate for efficiently developing a third generation high-density linkage map.