QTL analysis for production traits in Japanese quail using RAD-seq

Japanese quail (Coturnix japonica) is a model animal of chickens that also belong to family Phasianidae and can be used for production (meat/egg) purposes and biological researches. Production traits are the most important economic traits in poultry breeding industry. Both growth- and egg-related traits are complex traits influenced by genetic and environmental factors and their interactions. Quantitative trait locus (QTL) analysis is a method to find out QTLs that genetically control the traits. In QTL analysis, the chromosomal position of useful loci is identified based on DNA markers including single nucleotide polymorphisms (SNPs). SNPs are currently the marker of choice in many studies including genetics, biomedicinal, ecology, and evolutionary biology. Restriction-site associated DNA sequencing (RAD-seq) is a useful method that can identify, verify, and score thousands of SNPs simultaneously, reduce complexity across genome, deliver high-resolution population genomic data, and is convenient for non-model species at a reasonable cost. Identifying and mapping of genetic markers underlying QTLs can improve production traits in Japanese quail, and finally can improve the selection response in poultry breeding programs via marker-assisted selection (MAS). Therefore, this study was designed to discover QTLs associated with growth- and egg-related traits in Japanese quail using SNPs markers developed by RAD-seq.