Identification of quantitative trait loci affecting carcass traits and internal organs on chromosome two in Japanese quail

The aim of present research was to locate genomic loci (QTL) on chromosome 2. Itis associated with the carcass traits in Japanese quail. The F1 population was created by using reciprocal crosses between two strains of white birds (layer) and wild (broiler) birds. The F2 birds (422 birds) were derived by random mating of the F1 birds. All of the F2 birds were slaughtered at 35 days of age and recorded for carcass traits. Blood samples were collected at slaughtering time to genotype for four microsatellite markers on chromosome 2. Genotypic and phenotypic data were analyzed for QTL mapping with interval mapping method based on regression applying three different genetic models. A total number of 15 loci was found to be significantly associated with carcass traits. In the first model all traits with dominance effect were significant. The second model often had significant QTL with dominance and imprinting effects and all the traits were closest to the GUJ0084 marker. When it comes to the third model, most of the traits were significant in the female with dominance effect. Results of this study showed the role of Non-Mendelian inheritance (genomic imprinting) and pleiotropy as well as single gene effects in some traits.