Canine DNA Coat Color Testing
DDC Veterinary offers DNA testing for coat color genotypes among several dog breeds. By identifying the color genotype of the parents, clients can more accurately predict the colors of future progeny. Breeders can use DNA testing as a tool to more effectively manage mating patterns and make more informed selection decisions.
Coat Color DNA Testing options include:
E Locus (DNA marker tested – R306ter)
Most often used to determine the relationship of the Black (dominant) to Yellow (recessive). The ee genotype results in a yellow phenotype. (“Yellow” can represent a variety of lighter colors including apricots, reds, creams, and whites)
- EE – does not carry yellow
- Ee – yellow carrier
- ee – yellow phenotype
B Locus (DNA markers tested – S41C, P345Pel, Q331X)
Associated with the presence of chocolate (also commonly referred to as liver or brown). The bb genotype usually results in a chocolate coat phenotype and liver noses among yellow dogs.
- BB – does not carry brown
- Bb – brown carrier
- Bb2 – brown carrier
- bb – brown phenotype
For example, with Labrador Retrievers there are 3 accepted coat color phenotypes (what you can see): Black, Yellow, and Chocolate. However, there are 9 possible reported genotypes (what you cannot see) for the E and B loci and therefore 81 possible breeding combinations.
- Black Coat: 4 possible genotypes- EEBB (black with no hidden colors), EeBB (black with hidden yellow), EEBb (black with hidden chocolate), EeBb (black with hidden yellow and chocolate)
- Yellow Coat: 3 possible genotypes- eeBB (yellow with hidden black), eeBb (yellow with hidden black and chocolate), eebb (yellow with hidden chocolate- dogs will exhibit liver noses)
- Chocolate Coat: 2 possible genotypes- EEbb (chocolate with no hidden colors), Eebb (chocolate with hidden yellow)
Click here to view our Coat Color Predictor Chart. (Requires the free Adobe Reader to view.)
D Locus (DNA marker tested – C.22G>A)
Associated with the dilution or lightening effect of solid colors, with D being the dominant allele, the dd genotype results in the diluted effect (like grey, blue, silver, lilac, champagne).
- DD – does not carry dilute
- Dd – dilute carrier
- dd – dilute phenotype
Em Locus (DNA marker tested – M264V)
This allele allows the agouti protein to bind some of the time and cause fawn/red pigment to be made on the body and the melanocyte stimulating hormone to bind on the face instead. Dogs that are black, brown or blue do not show their mask against their similar body color. The mask is inherited as a dominant trait.
- EmEm – the dog is masked and has 2 copies of the dominant allele
- EmEx – the dog is masked & has 1 dominant allele & 1 recessive allele
- ExEx – the dog does not have a mask & has 2 recessive alleles
H locus (DNA marker tested – PSMB7:c.146T>G) Harlequin
Merle-colored Great Danes have dark spots on a diluted/grey background. The Harlequin gene causes a white background and the spots increase in size. Dogs that are not merle, cannot express the Harlequin color/pattern. Breeding two dogs that both have a copy of the H locus “NH” is not recommended. A dog with two copies of Harlequin has not been observed and It is presumed to be lethal in utero. This gene is inherited as a dominant trait.
- NN – 2 copies of the non-harlequin allele
- NH –1 copy of the non-harlequin allele & 1 copy of the harlequin allele, harlequin is expressed if merle gene is also present
- HH – 2 copies of the harlequin allele, lethal in utero
S Locus (DNA marker – MITF reference: Schmutz S, TG Berryere and DL Dreger. MITF and white spotting in dogs: a population study. Journal of Heredity 2009, 100(Supl 1):S66-S74.)
This allele is associated with Piebald, Parti, Landseer or Random White Spotting among several breeds where these patterns are observed. The inheritance and expression can vary depending on the breed. For example, the gene is most often recessive in nature, however in some breeds such as Collie, Great Dane, Italian Greyhound, Shetland Sheepdog, Boxer, and Bull Terrier, an animal having 1 copy of the piebald allele can exhibit some limited piebald expression.
NN – 2 copies of the non-piebald allele
N/S – 1 copy of the non-piebald allele and 1 copy of the piebald allele
S/S – 2 copies of the piebald allele
KB Locus (DNA marker – G23del)
The KB is responsible for allowing solid colors to be expressed in the dominant form of the allele (KB). In it’s homozygous recessive form (ky) allows the agouti (a, ay, at loci) colors to be expressed.
KBKB – 2 copies of the dominant allele
KBky – 1 copy of the dominant allele and 1 copy of the wild type
kyky – 2 copies of the wild type
ay Locus (DNA marker tested – A82S)
This agouti allele is responsible for fawn in breeds like the Pug or sable in breeds like the Collie.
- ayay - 2 copies of the fawn/sable allele
- ayaw - 1 fawn/sable allele and 1 non- fawn/sable allele
- awaw - 2 non-fawn/sable alleles
a Locus (DNA marker – R96C)
This agouti allele is responsible for recessive black. In the homozygous form aa, it will cause a recessive form of black coat in breeds like the German Shepherd Dog.
aa – 2 copies of the recessive black allele
aax – 1 copy of recessive black allele and 1 copy of the non-recessive black allele
axax – 2 copies of the non-recessive black allele
at Locus (DNA marker – ASIP reference: Schmutz S and DL Dreger. A SINE Insertion Causes the Black-and-Tan and Saddle Tan Phenotypes in Domestic Dogs. Journal of Heredity 2011, 102(S1):S11-S18.)
This color allele is associated with generating the commonly known phenotypes known as "tan points", "phantom" and "tri-color" among several breeds. The inheritance and expression can vary depending on the breed.
awaw – 2 copies of the non-tan point allele
awat - 1 copy of the non-tan point allele and 1 copy of the tan point allele
atat - 2 copies of the tan point allele
Highlights regarding this new test include:
- DNA samples can be collected easily at home using buccal (cheek) swabs.
- Dogs can be DNA tested at ANY age using the buccal swabs.
- The cost for testing is $58 (US) per canine for the first locus test and $20 for each subsequent coat color locus tested at the same time of sample submission. Also, a $10 discount per test for 5 or more samples submitted at the same time (order form will calculate testing fees).
- DNA results are emailed within 5 business days of receipt of the samples