| First Author | Drudik DK | Year | 1995 |
| Journal | J Anim Sci | Volume | 73 |
| Issue | Suppl 1 | Pages | 110 (Abstr.) |
| Mgi Jnum | J:35301 | Mgi Id | MGI:82751 |
| Citation | Drudik DK, et al. (1995) Identification of major genes controlling body weight and fat percentage on mouse Chromosome 2. J Anim Sci 73(Suppl 1):110 (Abstr.) |
| abstractText | Full text of Abstract: Identification of major genes controlling body weight and fat percentage on mouse chromosome 2. D.K. Drudik1,* D. Pomp1, Z-B. Zeng2, and E.J. Eisen3, Department of Animal Science, Oklahoma State University1, Stillwater, and Departments of Statistics2 and Animal Science3, North Carolina State University, Raleigh. The objective of this study was to pinpoint the chromosomal location of quantitative trait loci (QTL) for body weight and fat percentage in mice. To accomplish this, two unique inbred lines of mice were used: M16l (long-term selection for rapid 3-6 wk weight gain, characterized by high body weights and fat carcasses) and Mus musculus castaneus (CAST; wild origin, characterized by low body weights and lean carcasses). A large F2 backcross population (M16l x M16l/CAST; n=421) was produced. Body weight (BW) and gonadal fat pad weight/BW (FAT) were measured at 12 wk. Initially, genotypes were identified at three evenly spaced polymorphic microsatellite markers on each of the 19 mouse autosomes, using PCR and agarose gels. Marker effects were analyzed with least-squares procedures. Evidence for a region harboring a QTL with very large effects was observed on distal Chromosome 2, with differences of at least 4.0 BW (10% of the mean; P<.0001) and 0.55% FAT (39% of the mean; P<.0001) between M16l/M16l and M16l/CAST backcross mice. To determine more precisely the chromosomal location of this putative major QTL, genotypes at ten additional markers on Chromosome 2 were determined. A combination of interval analysis and multiple regression was used to localize the QTL. Evidence for two QTL was found, each with major effects on BW and FAT, with peaks between markers at 56 to 65cM from the telomere for the more proximal QTL (LOD scores 6.1 and 4.1 for BW and FAT, respectively) and 77 to 90 cM for the more distal QTL (LOD scores 3.5 and 4.3 for BW and FAT, respectively). Candidate genes for these QTL include the growth hormone releasing hormone (GHRH) and agouti loci. PCR-based markers are currently under development for each of these candidate loci These results indicate that there are potentially two genes with major effects on body weight and fat percentage on mouse Chromosome 2. Candidate chromosomal regions in livestock species that harbor homologues of these QTL will be identified using comparative mapping. Key Words: Quantitative Trait Loci, Growth, Obesity |
