Description:  Colour dilution is inherited autosomal recessive, that is, recessive homozygous dd is able to dilute eumelanin (Drogemuller et al., 2007a). In addition to d1, another allele d2 was found in three breeds Chow-chow, Sloughi, and Thai ridgeback. In these breeds, dilution was observed with a combination of d2d2 or d1d2 genotypes. The d2 mutation is associated with variant c. 705 G> C. The mutation probably affects MLPH mRNA splicing.

Currently, 3 variants (alleles d1, d2, and d3) caused by three different mutations have been identified in locus D. The d1,d2, and d3 variants are analyzed separately (three different analyzes).

Allele d1: c.-22G>A in MLPH gene

Allele d2: c.705G>C in MLPH gene

Allele d3: c.667_668insC in MLPH gene

Inheritance: autosomal recessive

Mutation (d2): c.705G>C in MLPH gene

Sample: EDTA whole blood (1.0 ml) or 2 buccal brushes

The analysis is suitable for the following breeds: Chow Chow, Sloughi, Thai Ridgeback, French Bulldog – in these breeds, a combination of the alleles d1/d2 may occur – these dogs may also have diluted coat color

Notes: So far, alleles d1, d2, and d3 have been identified. Additional gene variants responsible for color dilution are expected to occur in other breeds.