In addition to other new test results for coat colors, one more test result is now available for all MyDogDNA 2015 tested dogs:
Color Pattern (RALY gene): Saddle Tan
To learn more about what this result means, read the test description below:
"RALY gene defines whether tan points or saddle tan is expressed in the dog's phenotype in breeds that express both colors.
The color and pattern of a dog's coat depend on the combined effects of many different genetic factors. Saddle tan and tan point phenotypes are inherited together with the at allele at the A locus. 16bp duplication in intron 5 of the RALY gene in homozygous state is associated with tan point phenotype in Basset Hound and Pembroke Welsh Corgi.
Black and tan color is characterized by light color on the muzzle, above the eyes (tan points) and on the undersides of the dog on otherwise dark coat. Saddle tan resembles black and tan color but the lighter areas are expanded leaving usually only the back to have dark patch.
In order for the saddle tan pattern or tan points to be expressed, the dog needs to have at least one copy of the Em or E allele at the E locus, ky/ky genotype at the K locus and at/at or at/a genotype at the A locus.
The saddle tan phenotype requires one or two copies of the wildtype RALY gene without the duplication. The saddle tan phenotype is present in a limited number of dog breeds including some of the terriers, scent hounds and herding dogs. The saddle tan pattern develops as the dog ages from a puppy to an adult dog. In young puppies the saddle tan pattern resembles tan point phenotype.
Tan points are expressed in the dog’s phenotype if the dog has two copies of the duplication in the RALY gene. However, breeds that have only tan point phenotype and no saddle tan phenotype, tan pointed dogs can have any RALY genotype from the three possible options. This suggests that more complex interactions are behind tan points in breeds that are not able to express saddle tan."