Table 1. Loss-of-function phenotypes of melanogenesis genes across vertebrates.

Gene	Species with identified loss-of-function variants		Role of protein	Loss-of-function phenotype
TYR	Fish	Japanese carp [35], Japanese rice fish [36]	Rate-limiting enzyme in melanin synthesis pathway	Severe loss of melanin
	Frogs and snakes	Japanese wild frogs (three species) [37], Japanese rat snake [38]
	Birds	Chicken [39–41]
	Ungulates	Water buffalo [42], Cattle [43], Red deer [44], Asinara donkey [45]
	Rodents	House mouse [46], Wistar rat [47], Domestic guinea pig [48]
	Primates	Crab-eating macaque [49], Capuchin monkey [50], Hamadryas baboon [51], Human [reviewed in 52]
	Other mammals	Humpback whale [53], Ferret [54], American mink [55], Domestic cat [56–58], Silver fox [59]
OCA2	Fish	Mexican cavefish [60], Lake Malawi cichlid [61]	Cl- channel regulating melanosome pH	Moderate loss of melanin
	Snakes	Corn snake [62]
	Mammals	Domestic dog [63], Bama miniature pig [64], House mouse [65], Human [reviewed in 52]
TYRP1	Fish	Zebrafish [66]	Enzymes contributing to melanin synthesis	Mild loss of melanin
	Birds	Saker falcon [67]
	Mammals	Chinese indigenous pig [68], Liangshan pig [69], Domestic dog [reviewed in 70], Domestic cat [58,71], Soay sheep [72], Valais Red sheep [73], American mink [74], Human [reviewed in 52]
TYRP2	Mammals	House mouse [75,76]
SLC7A11	Mammals	House mouse [77]	Solute transporters
SLC24A5	Fish	Zebrafish [78]
	Mammals	Horse [79], Human [reviewed in 52]
SLC45A2	Fish	Japanese rice fish [80]
	Birds	Chicken and Japanese quail [81]
	Mammals	Domestic dog [82], Horse [83], House mouse [84], Bengal tiger [85], Western lowland gorilla [86], Human [reviewed in 52]