Decoding Your Dog's Coat Type and Length - Phenotype Impacted by Genotype

 

Dog Coat Type and Length

In honor of DNA Day on April 25, we are highlighting one of the most commonly observed traits in dogs, their unique coat types and explaining the underlying science that determines the outcome. Coats come in a variety of forms ranging from the short, hard, wiry coats of terriers to the long, silky coats of many toy dogs. Part of a dog’s coat can also include furnishings, which can include a moustache, beard, and eyebrows around the head.

An Embark for Breeders DNA Test Kit identifies eight different canine coat phenotypes that are a result of different combinations of three specific loci at the FGF5, RSPO2, and KRT71 genes. Ever wonder why a Basenji has a short, straight coat? Or why a poodle has a long, curly coat? Or simply why does a dog look the way it does? In reference to the infographic above, we take a closer look at some specific breeds’ phenotypes and the genotypes that influence the type and length we see and feel as we stroke the dog’s coat. These breeds were selected because they represent each phenotype well, not because they have all possible allele combinations. 

Basenji This breed represents the short, no furnishings, straight coat phenotype. The Basenji’s short-haired coat developed from its history as a small hunting dog in Africa. This coat phenotype can be a result of a GG or GT genotype at the FGF5 locus, an II genotype at the RSPO2 locus, and a CC, CT, or TT genotype at the KRT71 locus. Dogs of various breeds that have the curly (T) allele at KRT71 may still have a phenotypically straight coat if short in length.

Chesapeake Bay Retriever This breed represents the short, no furnishings, curly coat phenotype. The Chesapeake Bay Retriever’s curly, dense coat developed from its history hunting in very adverse icy winter weather around Maryland’s eastern shore. This coat phenotype can be a result of a GG or GT genotype at the FGF5 locus, an II genotype at the RSPO2 locus, and a TT or CT genotype at the KRT71 locus. The lack of furnishings make this breed stand out for their distinctive smooth face and muzzle.

Cairn Terrier This breed represents the short, furnished, straight coat phenotype. The Cairn’s hard, weather-resistant coat developed from its history excavating vermin in the rugged, natural landscape of the Scottish Highlands. This coat phenotype can be a result of a GG or GT genotype at the FGF5 locus, an FI or FF genotype at the RSPO2 locus, and a CC genotype at the KRT71 locus. It is important to note that some dog breeds, like the Berger Picard, that have the furnished (F) allele at RSPO2 may have a slight wave in their coat despite their CC KRT71 genotype. 

Belgian Laekenois  This breed represents the short, furnished, curly coat phenotype. The Laekenois’ rough and coarse coat developed from its history herding and guarding flocks in the Belgian countryside at the Royal castle of Laeken. This coat genotype can be a result of a GG or GT genotype at the FGF5 locus, an FI or FF genotype at the RSPO2 locus, and a TT or CT genotype at the KRT71 locus. 

Bernese Mountain Dog This breed represents the long, no furnishings, straight coat phenotype. The Bernese Mountain Dog’s thick, heavy coat developed from its history working as draft, drover, and watchdogs in the farmlands of Switzerland. This coat phenotype can be a result of a TT genotype at the FGF5 locus, an II genotype at the RSPO2 locus, and a CC genotype at the KRT71 locus. 

Maltese This breed represents the long, furnished, straight coat phenotype. The Maltese’s long, silky coat developed from its history as a prized companion of Greek and Roman women who treasured these small companions. This coat phenotype can be a result of a TT genotype at  the FGF5 locus, an FI or FF genotype at the RSPO2 locus, and a CC genotype at the KRT71 locus. It is important to note that some dog breeds that have the RSPO2 furnished (F) allele may have a wavy coat despite their CC KRT71 genotype, such as the Bearded Collie.

Irish Water Spaniel This breed represents the long, no furnishings, curly coat phenotype. The Irish Water Spaniel’s dense, tight body curls and smooth-faced coat developed from its history plunging into cold Irish bogs retrieving upland game. This coat phenotype can be a result of a TT genotype at the FGF5 locus, an II genotype at the RSPO2 locus, and a TT or CT genotype at the KRT71 locus. 

Poodle This breed represents the long, furnished, curly coat phenotype. The Poodle’s curly, harsh textured coat with furnishings developed from its history as a hunting retriever across Europe. This coat phenotype can be the result of a TT genotype at the FGF5 locus, an FI or FF genotype at the RSPO2 locus, and a TT or CT genotype at the KRT71 locus. 

There is so much more to learn about coat length and type in dogs. Check out our traits list for breeders to learn about all the traits Embark tests for. By collecting a robust number of canine population-wide DNA samples, purebred dog owners and breeders can contribute to the Embark database and help the research community discover more about what makes a dog’s coat unique to its breed.  

 

Let's Get Started

Order now