Test Detail

Mutation causing hairlessness in the Sphynx cat

Dermatológico · Cat

Genetic test of the variant that determines the hairlessness characteristic of the Sphynx cat. The mutation affects the KRT71 gene, which encodes a hair follicle keratin, and alters normal hair development, leaving an almost bare coat with fine down in some areas. It is not a disease: it defines a breed phenotype with specific dermal care. The test makes it possible to plan crosses and anticipate whether the offspring will have hair or not.

Inheritance pattern	Autosomal recessive (hr/Re^HR allele; hierarchy KRT71+ > hr > re with respect to the Devon Rex allele).
Gene / Mutation	KRT71 c.816+1G>A (g.78941699C>T in Fca126_mat1.0), splice site substitution; hr allele (Re^HR) of the Sphynx. OMIA:001583-9685 (variant 382). The wavy coat of the Devon rex is due to another allele of the same gene (re): c.1108-4_1184del, c.1184_1185insAGTTGGAG and c.1196insT (OMIA:001581-9685, variant 380); allele hierarchy + > hr > re.
Penetrance	Complete in homozygotes for the Sphynx variant: hairless coat. Heterozygotes have hair, sometimes with a slightly altered texture depending on their genetic background.
Code	uenz
Turnaround time	10 days
Price	76,07 €

Incidence

The variant is essentially fixed in the purebred Sphynx population, where the hairless phenotype is the standard. Heterozygotes appear in outcross programs (Devon Rex and domestic shorthair in some registries). As it is a desired and selected trait, it is not appropriate to speak of disease incidence.

Breeder management

- Two homozygous Sphynx produce hairless offspring consistently\n- If you cross a Sphynx with a normal-haired non-carrier cat, the entire first generation will have hair and will be carriers\n- Crossing Sphynx with Devon Rex can produce hairless cats (compound heterozygotes) due to allelism at KRT71: know your registry's rules on these outcrosses\n- Use the test to confirm the status before planning outcrosses or importing new lines\n- Do not prioritize the hairless phenotype over cardiac health: maintain HCM screening in the breed

Specialist notes

Do not confuse the KRT71 phenotype with other feline hypotrichoses of a different cause or with acquired alopecias (demodicosis, dermatophytosis, psychogenic alopecia). Sphynx skin requires regular hygiene to prevent sebaceous dermatitis and secondary infections, sun protection and environmental thermal control. From a welfare perspective, inform owners of the maintenance the breed requires before acquisition.

References

1. Gandolfi B, Outerbridge CA, Beresford LG, Myers JA, Pimentel M, Alhaddad H, Grahn JC, Grahn RA, Lyons LA. The naked truth: Sphynx and Devon Rex cat breed mutations in KRT71. Mamm Genome 21(9-10):509-515, 2010. PMID: 20953787
2. Lyons LA. DNA mutations of the cat: the good, the bad and the ugly. J Feline Med Surg 17(3):203-219, 2015. PMID: 25701860
3. OMIA:001583-9685. Hypotrichosis, with whiskers short and curled in Felis catus. https://omia.org/OMIA001583/9685/
4. OMIA:001581-9685. Curly coat, Devon rex in Felis catus. https://omia.org/OMIA001581/9685/

Add to cart

← Back to the search