D-Locus (dilute)


Turnaround: 10-15 business days

Not sure how the process works? Have a read of our Frequently Asked Questions.

The D-locus is a region of your dog's DNA which controls whether your dog will have a diluted coat colour. This is not a colour in itself, but will lighten the coat colour caused by the E-Locus, B-Locus, or A-Locus. In some breeds this is known as blue, lilac or isabella. In dilute dogs, their eyes will also lighten to an amber colour.

Dogs which carry one or two copies of dilute (d) can produce dilute puppies if they are bred to a dilute or dilute carrying dog. If your dog does not carry any copies of dilute they don't have a dilute coat and can't pass it on to their puppies.

The dilute coat colour is also associated with hair loss known as colour dilution alopecia (CDA) and black hair follicular dysplasia (BHFD) in some breeds.

Your dog can only be dilute if they are d/d at the D-locus, and the final diluted colour will depend on the E-Locus, B-Locus, and A-Locus.

The dilution colour is caused by mutations on the MLPH gene. Dilution is recessive meaning two copies of d are required to cause the diluted coat colour.


Your results will be reported as one combination of the D-locus alleles with the following interpretations.

D/D - non-dilute
D/d - non-dilute carrying dilute
d/d - dilute


Scientific References:

Schmutz SM and Berryere TG (2007). Genes affecting coat colour and pattern in domestic dogs: a review. Anim. Genet. 38, 539-549.