Long hair

The length of the coat covering the body, limbs, and tail of the dog is related to a single gene, called FGF5.

Definition

The trait refers to the variant causing long hair in the body, legs, and tail. The variant is found in the FGF5 gene, which is involved in regulating hair growth in the hair follicle.

Genetic basis

Several genetic variants in the FGF5 gene have been identified that affect coat length in dogs. In this study, we analyzed three of the most well-known variants: c.578C>T, c.284G>T, and c.556_571del. This trait follows an autosomal recessive inheritance pattern, meaning that a long, silky coat will only be expressed in dogs that have two copies of any of these three variants. It is also possible for the coat to be long if the dog has one copy of two different variants, which is known as compound heterozygosity. If the dog has only one copy of the c.578C>T, c.284G>T, or c.556_571del variants, its coat will be short, but that variant can be passed on to offspring with a 50% probability. However, it is possible for the coat to be long if any of these variants combine in compound heterozygosity with another variant not analyzed in this study.

Other relevant information

Long hair in dogs can be described as fluffy (in Corgis) or woolly. The c.556_571del variant has been observed exclusively in the Eurasier breed, while the c.578C>T variant has been identified in breeds such as the Akita, Samoyed, and Siberian Husky. However, these two variants are not as common as the c.284G>T, which has been detected in a wide variety of breeds, including the Afghan Hound, Border Collie, Cocker Spaniel, Collie, Dachshund, German Shepherd, Golden Retriever, Pomeranian, and Samoyed.

Bibliography

Cadieu E, Neff MW, Quignon P, et al. Coat variation in the domestic dog is governed by variants in three genes. Science. 2009 Oct 2