Comparative transcriptome profiles of Lindian chicken eyelids identify melanin genes controlling eyelid pigmentation. Gallus gallus

During the long history of chicken domestication, eyelid color, like skin color and shank color, has been one of the unique physical traits of Chinese indigenous chickens that influence consumer behavior. In China, the Lindian chicken, which has colored feathers, is renowned for the appetizing flavor of its meat and eggs, and its eyelid colors varies from deep to light shades, including black, gray, red, and light yellow. To identify the genes controlling eyelid pigmentation, the expression profiles of black and light-yellow eyelids of Lindian chickens were analyzed with transcriptome sequencing. We detected 13,466 genes expressed in the eyelids, among which 14 were differentially expressed. A KEGG pathway analysis showed that tyrosine metabolism and melanogenesis genes were significantly enriched among these DEGs (corrected P < 0.05). Therefore, we infer that melanin metabolism is one of main factors affecting Lindian chicken eyelid pigmentation. In summary, we have identified the melanin genes responsible for eyelid pigmentation of the Lindian chicken, and also provide a valuable resource for the future study of the physical traits of chickens. Overall design: Examination of 6 mRNA expression in black and light-yellow eyelid of Lindian chickens.