A New Mutation in MC1R Explains a Coat Color Phenotype in 2 “Old” Breeds: Saluki and Afghan Hound

Abstract

Melanocortin 1 Receptor (MC1R) has been studied in a wide variety of domestic animals (Klungland et al. 1995; Marklund et al. 1996; Våge et al. 1997; Kijas et al. 1998; Newton et al. 2000; Våge et al. 2003), and also several wild animals (Robbins et al. 1993; Ritland et al. 2001; Eizirik et al. 2003; Nachman et al. 2003; McRobie et al. 2009) in relation to coat color variation. A variety of phenotypic changes have been reported including coat colors from pure black to pure red, as well as some phenotypes with hairs with red and black bands. One phenotype, called grizzle in Salukis and domino in Afghan Hounds, appears to be unique to these 2 old dog breeds. This pattern is characterized by a pale face with a widow's peak above the eyes. The body hairs on the dorsal surface of Salukis and Afghan Hounds have both phaeomelanin and eumelanin portions, even though they had an a(t)/a(t) genotype at ASIP. In addition, all had at least one copy of a newly identified mutation in MC1R, g.233G>T, resulting in p.Gly78Val. This new allele, that we suggest be designated as E(G), is dominant to the E and e (p.Arg306ter) alleles at MC1R but recessive to the E(M) (p.Met264Val) allele. The K(B) allele (p.Gly23del) at DEFB103 and the a(y) allele (p.Ala82Ser and p.Arg83His) of ASIP are epistatic to grizzle and domino.