Long Hair/Fluffy
Affected Gene: FGF5
Transmission: Autosomal recessive
Mutation: CanFam3.1 32 g.4509367G>T c.284G>T
OMIA Link: 000439-9615

Breeds Recommended for Testing:  Several breeds, including:
Afghan Hound, Border Collie, Cocker Spaniel, Collie, Corgi, Dachshund, German Shepherd, Golden Retriever
Pomeranian, Samoyed, Shiba Inu

Description:
The L locus impacts the length of canine hair due to a mutation in the FGF5 gene, which prevents FGF5 from functioning as a growth termination signal in the hair follicle. This leads to longer hair and fluffier coats in affected dogs.

References:
Cadieu E, Neff MW, Quignon P, Walsh K, Chase K, Parker HG, VonHoldt BM, Rhue A, Boyko A, Byers A, Wong A, Mosher DS, Elkahloun AG, Spady TC, Andre C, Lark KG, Cargill M, Bustamante CD, Wayne RK, Ostrander EA.
Coat variation in the domestic dog is governed by variants in three genes.
Science. 2009 Oct;326(5949):150-3.
Dierks C, Momke S, Philipp U, Distl O.
Allelic heterogeneity of FGF5 mutations causes the long-hair phenotype in dogs.
Anim Genet. 2013 Aug;44(4):425-31.
Housley DJ, Venta PJ.
The long and short of it: evidence that FGF5 is a major determinant of canine ‘hair’-itability.
Anim Genet. 2006 Aug;37(4):309-15.