Cat Coat color – D locus (Dilute)
The dilute phenotype in the domestic cat appears as a dilution of expected coat color and affects both eumelanin and phaeomelanin. As two examples, the dilution of black results in a gray phenotype (termed “blue” by cat breeders), while dilute combined with orange appears as a cream colour, chocolate results in lilac, cinnamon results in fawn and orange in creme. MLPH protein is one of the critical components essential for even distribution and transport of pigment granules in the skin. When MLPH gene on D locus is mutated, pigment granules are clumped and distributed unevenly along the hair shaft, which results in coat color dilution. In cats, dilute is inherited in an autosomal recessive pattern, meaning that in order for cat to express dilute coat color, has to have two d alelles ( genotype dd). Can can be heterozygous on D locus ( genotype Dd), which means the cat will be the d gene carrier but without its expression.
Ishida, Y., David, V.A., Eizirik, E., Schäffer, A.A., Neelam, B.A., Roelke, M.E., Hannah, S.S., O’brien, S.J., and Menotti-Raymond, M. (2006). A homozygous single-base deletion in MLPH causes the dilute coat color phenotype in the domestic cat. Genomics 88, 698–705.