| Other Names: | Long hair trait, Longhaired trait, Short hair trait, L locus |
|---|---|
| Affected Genes: | FGF5 |
| Mutation(s): | Lh1 = c.G>T; g.chr32:4509367 (Common Variant); Lh2 = c.C>T; g.chr32:4528639 (Akita, Eurasier, Samoyed, and Siberian Husky type); Lh3 = c.16 bp deletion; g.chr32:c.556_571del16 (Eurasier type); Lh4 = c.2 bp duplication (dup GG); g.chr32:4528621-4528622 (Afghan Hound, Eurasier, and French Bulldog type) |
| Breed(s): | All breeds |
Testing Summary
The L Locus (Long Hair/Fluffy) trait test evaluates the L Locus for the Lh1, Lh2, Lh3, and Lh4 Mutations that have been associated with long hair. Long hair is also referred to as fluffy coat in some breeds. This test will reliably determine if a dog has one of the following genotypes at the L locus:
| Sh/Sh | This dog carries two copies of Sh which results in short hair. This dog will pass on Sh to 100% of its offspring. Interpretation: Shorthaired (does not carry long hair) |
| Sh/Lh1 | This dog carries one copy of the Sh and one copy of the Lh1 Mutation which results in short hair. This dog will pass one copy of Sh to 50% of its offspring and one copy of Lh1 to 50% of its offspring. This dog can produce Lh/Lh offspring if bred to a dog that is also a Carrier of an Lh mutation (Sh/Lh or Lh/Lh). Interpretation: Shorthaired (carries one copy of long hair) |
| Sh/Lh2 | This dog carries one copy of the Sh and one copy of the Lh2 mutation which results in short hair. This dog will pass one copy of Sh to 50% of its offspring and one copy of Lh2 to 50% of its offspring. This dog can produce Lh/Lh offspring if bred to a dog that is also a Carrier of an Lh mutation (Sh/Lh or Lh/Lh). Interpretation: Shorthaired (carries one copy of long hair) |
| Sh/Lh3 | This dog carries one copy of the Sh and one copy of the Lh3 mutation which results in short hair. This dog will pass one copy of Sh to 50% of its offspring and one copy of Lh3 to 50% of its offspring. This dog can produce Lh/Lh offspring if bred to a dog that is also a Carrier of an Lh mutation (Sh/Lh or Lh/Lh). Interpretation: Shorthaired (carries one copy of long hair) |
| Sh/Lh4 | This dog carries one copy of the Sh and one copy of the Lh4 mutation which results in short hair. This dog will pass one copy of Sh to 50% of its offspring and one copy of Lh4 to 50% of its offspring. This dog can produce Lh/Lh offspring if bred to a dog that is also a Carrier of an Lh mutation (Sh/Lh or Lh/Lh). Interpretation: Shorthaired (carries one copy of long hair) |
| Lh1/Lh1 | This dog carries two copies of Lh1 which results in long hair. This dog will pass one copy of Lh1 to 100% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh2/Lh2 | This dog carries two copies of Lh2 which results in long hair. This dog will pass one copy of Lh2 to 100% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh3/Lh3 | This dog carries two copies of Lh3 which results in long hair. This dog will pass one copy of Lh3 to 100% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh4/Lh4 | This dog carries two copies of Lh4 which results in long hair. This dog will pass one copy of Lh4 to 100% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh1/Lh2 | This dog carries one copy of the Lh1 and one copy of the Lh2 mutation which results in long hair. This dog will pass one copy of Lh1 to 50% of its offspring and one copy of Lh2 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh1/Lh3 | This dog carries one copy of the Lh1 and one copy of the Lh3 mutation which results in long hair. This dog will pass one copy of Lh1 to 50% of its offspring and one copy of Lh3 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh1/Lh4 | This dog carries one copy of the Lh1 and one copy of the Lh4 mutation which results in long hair. This dog will pass one copy of Lh1 to 50% of its offspring and one copy of Lh4 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh2/Lh3 | This dog carries one copy of the Lh2 and one copy of the Lh3 mutation which results in long hair. This dog will pass one copy of Lh2 to 50% of its offspring and one copy of Lh3 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh2/Lh4 | This dog carries one copy of the Lh2 and one copy of the Lh4 mutation which results in long hair. This dog will pass one copy of Lh2 to 50% of its offspring and one copy of Lh4 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
| Lh3/Lh4 | This dog carries one copy of the Lh3 and one copy of the Lh4 mutation which results in long hair. This dog will pass one copy of Lh3 to 50% of its offspring and one copy of Lh4 to 50% of its offspring. Interpretation: Longhaired (carries two copies of long hair) |
Detailed Summary
The L Locus impacts canine hair length as a result of DNA variants in the FGF5 gene that prevents FGF5 from functioning as a hair growth termination signal in the hair follicle.
Testing Tips
Genetic testing of the FGF5 gene will reliably determine whether a dog is a genetic Carrier of long hair. Long hair is inherited in an Autosomal Recessive fashion, meaning that two copies of the Lh variant are required to produce long hair. Dogs with two copies of the Lh variant of FGF5, therefore, have long hair due to the lack of the hair growth termination signal. Dogs with one copy of Lh or no copies of Lh will have short hair. However, this dog’s coat type is also dependent on the dog’s genotypes at many other genes.
Disclaimer:
There may be other causes of this color pattern in dogs and a normal result does not exclude a different Mutation in this gene or any other gene that may result in a similar genetic trait.
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. [PubMed: 19713490]
- 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. [PubMed: 23384345]
- 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. [PubMed: 16879338]
