Cat Coat Color - E locus (Extension/Amber)

Acronym:	E locus
Gene:	MC1R
Mutation:	c.250G>A
Inheritance:	Autosomal recessive
Sample type:	CHS (Cheek Swab), WBE (Whole Blood EDTA)

---

Genetics and characteristics

Coat color in cats is an important congenital characteristic along with hair length and growth pattern. Coat color is determined by the expression of two melanin pigments, eumelanin (black/brown) and pheomelanin (yellow/red) in a variety of mammalian species including cats. The Melanocortin 1 Receptor (MC1R) gene plays an essential role in the regulation of coat color determination and it is commonly referred to as the E (extension) Locus. It encodes the key signaling molecule on melanocytes and it controls the production and balance of the pheomelanin and eumelanin pigments. So far three variants of the MC1R gene have been detected in cats, in Burmese, Kurilian Bobtail, and Norwegian Forest breeds. The variant found in Norwegian Forest cats is a consequence of a single base pair change resulting in tabby kittens initially brown or blue and the brightening of the original color with age to an apricot/cinnamon-like color.

The amber color in Norwegian Forest cats has an autosomal recessive mode of inheritance meaning only cats with two mutated variants will show a yellowish coat color. Cats that are carrying only one mutated gene will not show a yellow phenotype but will act as carriers of the specific mutation in the MC1R gene and potentially pass it to their offspring. Since this type of yellow coat color phenotype develops later with age, genetic testing can identify carriers and help breeders in future mating pairs selection.

 

---

Results Reported As

 

 

 

 

 

 

 

 

 

 

---

References:

Peterschmitt, M., Grain, F., Arnaud, B., Deléage, G., Lambert, V. (2009). Mutation in the melanocortin 1 receptor is associated with amber colour in the Norwegian Forest Cat. Animal genetics, 40(4), 547–552. https://doi.org/10.1111/j.1365-2052.2009.01864.x