Allelic heterogeneity of FGF5 mutations causes the long-hair phenotype in dogs

Anim Genet. 2013 Aug;44(4):425-31. doi: 10.1111/age.12010. Epub 2013 Feb 6.


Hitherto, the only known mutant gene leading to the long-hair phenotype in mammals is the fibroblast growth factor 5 (FGF5). In many dog breeds, the previously discovered FGF5:p.Cys95Phe mutation appeared completely concordant with the long-hair phenotype, but for some breeds, the long-hair phenotype could not be resolved. First, we studied the role of the FGF5:p.Cys95Phe and FGF5:g.145_150dupACCAGC mutations in 268 dogs descending from 27 breeds and seven wolves. As these mutations did not explain all the long-hair phenotypes, all exons and their neighbouring regions of FGF5 were re-sequenced. We detected three novel mutations in the coding sequence and one novel non-coding splice-site mutation in FGF5 associated with the long-hair phenotype. The FGF5:p.Ala193Val polymorphism was perfectly consistent with long hair in Akitas and probably in Siberian huskies, too. Dogs of the long-hair breed Samoyed were either homozygous or compound heterozygous for the FGF5:p.Ala193Val or the FGF5:p.Cys95Phe polymorphisms respectively. The two newly detected polymorphisms FGF5:c.559_560dupGG and FGF5:g.8193T>A and the known mutation FGF5:p.Cys95Phe explained the long-hair phenotype of all Afghan hounds analysed. An FGF5:c.556_571del16 mutation was found in one longhaired Eurasier. All long-hair-associated mutations follow a recessive mode of inheritance, and allelic heterogeneity was a common finding in breeds other than Akita.

Keywords: ancient dog breeds; coat variation; fibroblast growth factor 5.

MeSH terms

  • Animals
  • DNA, Complementary / chemistry
  • DNA, Complementary / genetics
  • Dogs / genetics*
  • Dogs / growth & development
  • Fibroblast Growth Factor 5 / genetics*
  • Gene Frequency
  • Genetic Heterogeneity
  • Hair / growth & development*
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Polymerase Chain Reaction / veterinary
  • Polymorphism, Genetic / genetics*
  • Polymorphism, Restriction Fragment Length
  • Sequence Analysis, DNA / veterinary
  • Species Specificity


  • DNA, Complementary
  • Fibroblast Growth Factor 5

Associated data

  • GENBANK/DQ268833