Comb and skin pigmentation are key external traits in domestic chickens, closely correlated and serving as important visual cues for consumers. The Anyi Gray chicken, an indigenous breed from Jiangxi Province, China, exhibits two stable phenotypes: red comb with white skin (RAY), and purple-gray comb with purple-gray skin (PAY). Although skin color is completely linked to comb color, the genetic basis of this coordination remains unclear. We performed whole-genome resequencing (∼ 10 × depth) on RAY and PAY individuals, followed by a case-control genome-wide association study (GWAS). A highly significant variant, g.10818413 T>C, located in the promoter region of EDN3 , was identified ( P C mutation reduces NFAT5 binding affinity, cis-regulating EDN3 transcription and driving the coordinated pigmentation of the comb and skin. This study reveals a shared regulatory mechanism underlying the phenotypic correlation between comb and skin pigmentation in Anyi Gray chickens.
Huang et al. (Sun,) studied this question.