In the present study, the association between a 24-bp Insertion-Deletion (Indel) in the prolactin receptor gene (PRL), and the polymorphic site NC_006091.5: c.25.144.C>A(T) in the melatonin receptor gene (MTNR-1C) was investigated in Japanese laying quails. In total, 396 female and 132 male quails were selected for the experiment. The number of eggs was recorded daily in individual quails for egg production and other reproductive traits. Every four weeks, one egg per quail was randomly selected for external and internal assessment. PCR-RFLP and PCR-SSCP were applied for genotyping the Indel, and the single nucleotide polymorphism in PRL and MTNR-1C genes, respectively. The data was continuously collected until 48 weeks of laying. For the effects of PRL Indel, it was found that DD genotyped quails provided a slightly higher egg yield in the first 24 laying weeks (155.1 eggs/quail); however, when the quails reached 36 and 48 weeks of laying, the difference in egg production was clear (P

Key words: Association, egg traits, Japanese quails, MTNR-1C, PRL