Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: January 15, 1999
Publication Date: N/A
Technical Abstract: A unique association of callipyge genotypes with phenotypes may involve the regulation of gene-expression by parental imprinting. Only individuals receiving the mutant callipyge allele from their sire, and a wild-type allele from their dam exhibit the callipyge phenotype. This phenotype is characterized by enhanced dressing percentage, lean growth rate, muscle shape and carcass composition but adverse effects on tenderness of specific muscles. Understanding the genetic basis for callipyge will allow exploitation of enhanced productivity of callipyge animals while minimizing the negative effects on meat quality traits. We have taken a directed approach to fine map the callipyge chromosomal region with the objective of cloning the gene. We have mapped the callipyge locus to a 3.9 cM interval on the subtelomeric portion of ovine chromosome 18. This interval was refined by constructing a radiation hybrid map of the region with available Type II genetic markers and several candidate genes selected from comparative maps. These genes were placed on the ovine and bovine genetic maps by development of microsatellite and SNP markers. These integrated maps facilitate rational selection of positional candidate genes from the gene-rich human and mouse genome maps.