Test Detail
e1 locus / K-locus — coat colour (Poodle)
General · Dog
Coat colour genetic test that determines the genotype of the Extension locus (E, MC1R gene) for the e1 allele (recessive red) and, depending on the panel, the K locus (Dominant Black, CBD103 gene) in the Poodle. The e1 allele in homozygosity (e1/e1) blocks eumelanin production and gives a red/apricot coat, characteristic of many lines of the breed. It is not a disease test: it informs about coat phenotype and allows colour matings to be planned. The commercial name combines the nomenclature of the E locus (e1) with that of the K-locus, both from the classic canine colour panel.
Incidence
Applicable breed: Poodle. The e1 allele is present and common in apricot and red coat lines of the breed; reliable carrier frequency figures from large series are not usually published. The e1 variant is also found in many other dog breeds (Golden Retriever, Labrador, Irish Setter, etc.).
Breeder management
- Genotype breeding animals for E and K before planning colour matings\n- Two E/e1 carriers mated together can produce red puppies (25 %) even if both parents have a dark coat\n- An e1/e1 with any carrier dark-coated partner can produce red\n- Remember K-locus epistasis: an e1/e1 homozygote no longer shows eumelanin, so the B and K genotype is masked in the phenotype\n- Do not prioritise coat colour over health or temperament criteria in selection
Specialist notes
Always interpret the result together with the other loci of the colour panel (B for brown, D for dilution, A for agouti). In the Poodle, apricot and red are e1/e1 phenotypes; white may be due to red intensity (modifiers not always tested) or to other loci. MC1R genotyping does not provide information on other loci unless tested separately. Do not extrapolate colour results to health conclusions.
References
1. Newton JM et al. 2000. Melanocortin 1 receptor variation in the domestic dog. Mamm Genome. PMID: 10602988
2. Everts RE et al. 2000. Identification of a premature stop codon in the melanocyte-stimulating hormone receptor gene (MC1R) in Labrador and Golden retrievers with yellow coat colour. Anim Genet. PMID: 10895310
3. Candille SI et al. 2007. A beta-defensin mutation causes black coat color in domestic dogs. Science. PMID: 17947548
4. Dürig N et al. 2018. Two MC1R loss-of-function alleles in cream-coloured Australian Cattle Dogs and white Huskies. Anim Genet. PMID: 29932470
OMIA001199-9615 / OMIA001416-9615.
2. Everts RE et al. 2000. Identification of a premature stop codon in the melanocyte-stimulating hormone receptor gene (MC1R) in Labrador and Golden retrievers with yellow coat colour. Anim Genet. PMID: 10895310
3. Candille SI et al. 2007. A beta-defensin mutation causes black coat color in domestic dogs. Science. PMID: 17947548
4. Dürig N et al. 2018. Two MC1R loss-of-function alleles in cream-coloured Australian Cattle Dogs and white Huskies. Anim Genet. PMID: 29932470
OMIA001199-9615 / OMIA001416-9615.