ENHANCING GENETIC MERIT OF DAIRY CATTLE THROUGH GENOME SELECTION AND ANALYSIS
Title: Whole genome analysis for backfat thickness in a tropically adapted, composite cattle breed from Brazil
| Veneroni Gouveia, G - |
| Meirelles, S - |
| Grossi, D - |
| Santiago, A - |
| Yamagishi, M.E. - |
| Matukumalli, Lakshmi - |
| Coutinho, L - |
| Alencar, M - |
| Oliveira, H - |
| Regitano, L.C. - |
Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 7, 2011
Publication Date: November 7, 2011
Citation: Veneroni- Gouveia, G., Meirelles, S.L., Grossi, D.A., Santiago, A.C., Sonstegard, T.S., Yamagishi, M.B., Matukumalli, L.K., Coutinho, L.L., Alencar, M.M., Oliveira, H.N., Regitano, L.A. 2011. Whole genome analysis for backfat thickness in a tropically adapted, composite cattle breed from Brazil. Animal Genetics. DOI: 10.1111/j.1365-2052.2011.02286.x.
Interpretive Summary: Among current cattle populations selected for beef production, a tremendous amount of genetic variation affecting product quality traits is still segregating in these populations. In this study, a tropically adapted breed of cattle was studied to try and determine the locations of some of these regions of the genome affecting carcass quality traits. Specifically, this study used a high-density genotyping platform that interrogated 50,000 locations of the genome and looked for association of certain DNA patterns with fat thickness. Two highly significant regions on chromosome 14 were identified. This information could potentially be used to accelerate genetic improvement for producing more desirable and highly valued beef products.
Backfat thickness affects preservation of the beef carcass after slaughter and confers organoleptic characteristics assessed by the consumer. One of the breeding goals for Canchim, a tropically adapted breed, is to comprehensively increase fat thickness. Our goal was to identify genomic regions associated with backfat in Canchim populations and validate the association of SNP (single nucleotide polymorphism) overlapping previously identified QTL regions known to affect fat deposition. Fifteen animals with lower and 15 animals with higher residues for backfat, according to a linear model using the SAS GLM procedure, were selected from a population of 1,171 animals and genotyped using the BovineSNP50 beadchip. Initial analysis revealed more than 100 SNP that discriminated the tails of phenotypic distribution. One extended region of association included the centromeric region of chromosome (Chr) 14. Because this region overlapped with QTL from previous reports, we developed SNP assays to interrogate two linkage disequilibrium blocks, one in the centromeric region and another in the middle region of Chr 14 to confirm the association. The analysis validated the presence of specific haplotypes affecting fat thickness.