Date of Award
Doctor of Philosophy
Max F. Rothschild
Jack C. M. Dekkers
Meat quality contributes considerably to the profit involved in pork production. The main objectives of this study were to identify the chromosomal locations for growth, body composition and meat quality related traits in pigs and to identify genes that control quantitative traits of economic importance. Genome scans were employed to identify these chromosomal regions. A three-generation resource family was developed using two Berkshire grand sires and nine Yorkshire grand dams. Data for 40 traits (growth, body composition and meat quality) were collected from 525 F2 progeny. Linkage analysis and regression interval mapping based on 125 microsatellite markers were used for QTL detection. Significance thresholds were determined by permutation tests. Significant QTL at the chromosome wise 5% level were detected for a total of over 100 growth (chromosomes 1, 2, 3, 4, 6, 7, 8, 9, 11, 13, 14, X), backfat (chromosomes 1, 4, 5, 6, 7, 10, 13, 14) and meat quality traits (chromosomes 1, 2, 4, 5, 6, 8, 10, 11, 12, 13, 14, 15, 17, 18, X). Five genes (ACACB, PPP1CC, GPR49, DUSP6, ATP2B1 ) from human chromosome 12 were chosen as possible candidate genes for QTL detected on chromosome 5. These genes were successfully mapped by physical and genetic methods. Two genes (DUSP6, ATP2B1) were considered for further positional candidate gene analysis. A ATP2B1-Afl III polymorphism revealed significant associations with growth, body composition, and meat quality traits (glycogen content and potential, and ham and loin pH) in the BxY F2 population, but only with light reflectance of ham in a commercial line. A DUSP6-Pst1 Polymorphism was associated with fat traits, which was consistent in the QTL analysis and association studies in the BxY family and in two commercial lines. The identified ATP2B1 and DUSP6 polymorphisms could potentially be used as a markers to track associated QTL and to discover the causative DNA differences.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu
Malek, Massoud, "A molecular genome scan and positional candidate gene analysis for important economic traits in the pig " (2001). Retrospective Theses and Dissertations. 1330.