Genetics of skin color in chickens

The phenotypic diversity of skin color in wild and domestic animals is an important characteristic for biologists and breeders. The color of the skin can be a sign of the breed. Some people prefer a bird with a dark skin color; such meat is considered more delicious and nutritious. In European countries, yellow-skinned or white-skinned birds are preferred.The variety of skin colors depends on a combination of specific genes that affect the deposition of xanthophylls and melanins, polygenic modifiers, and environmental factors. The yellow color of the egg yolk, as well as the white or yellow color of the skin and fat, is caused by carotenoids and xanthophylls. The dark colors of the skin and feathers depend on melanin, which is divided into eumelanin - the black pigment of the eyes, plumage, connective tissue and skin, and pheomelanin, which determines the brown shades of the plumage.Even in the last century, the Mendelian inheritance of white and yellow skin color in chickens was studied and the autosomal genes (W, w) that cause it were determined. Later in 2008, associations of the W locus with the beta-carotene dioxygenase 2 (BCDO2) gene were found. The results of these studies a