Identification of genetic loci associated with live body weight and carcass weight in red brown Korean native chickens

Body weight is an important quantitative trait controlled by genetic and environmental factors. The identification of genetic mechanisms influencing weight gain is important for improving the production of chicken meat. Thus, the aim of this study was to identify genetic loci associated with live body weight and carcass weight at the age of 10 weeks in the Red Brown Korean chickens. The body weight of 541 chickens was measured before slaughter. On the other hand, carcass weights for 637 chickens were obtained after slaughter. DNA samples were genotyped using the 60K Illumina SNP panel. Genome-wide association studies for the two traits were conducted separately using the mixed linear model. Two suggestively significant SNPs in chromosome 11 were associated with live body weight. As for carcass weight, seven suggestively significant SNPs were identified in chromosomes 1, 3 and 10. Several candidate genes, including the GLG-1, FHOD1 and AGRP, were associated with live body weight. Likewise, the genomic regions associated with carcass weight harboured notable genes, including HMG20A, TSPAN3, NRG4 and TBC1D2B. Furthermore, the identified SNPs were in QTL regions associated with growth traits in chickens. The results of this study provided insights into the genetic mechanisms influencing live body weight and carcass weight at 10 weeks of age in the Red Brown Korean native chickens. Further studies are warranted to verify the candidate genes’ role in the regulation of growth and weight gain in chickens.