Cocoa (Brown) Coat Colour

Test Overview:

A variant in the murine Hps3 gene has been found to cause brown coat color in the cocoa mouse mutant. This was genotyped in a population of 373 French Bulldogs and found a strong association of the homozygous mutant HPS3 genotype with the brown coat color. This brown is referred to as 'cocoa' in the french bulldog and tends to be slightly 'darker' than the regular brown/chocolate phenotype seen in other breeds.


Trait (Associated with Phenotype)



Variant Detected:

c.2420G>A or p.(Trp807*)


It is a trait and so is tested based on preference, not usually for health concerns.

Mode of Inheritance:

Autosomal Recessive with Incomplete Penetrance

Research Citation(s):

Genes 2020, 11(6), 636;

Associated Breed(s):

American Bulldog , American Bully , Boston Bulldog, British Bulldog, French Bulldog,