Genetic basis of Cornish Rex - The unique curly coat of Cornish Rex cats is caused by an autosomal recessive mutation in the lysophosphatidic acid receptor 6 (LPAR6) gene. This gene encodes a G protein-coupled receptor expressed in the inner root sheath of hair follicles, essential for maintaining the structural integrity of the hair shaft. The causal mutation is a 4 base pair deletion (c.250_253delTTTG) in exon 5 of LPAR6, which leads to a frameshift and premature stop codon, resulting in a nonfunctional receptor protein. Cats must inherit two copies of the mutated gene (homozygous) to express the characteristic curly (woolly) coat phenotype. Heterozygous cats (carriers) have normal straight coats but can pass the mutation to offspring.
Pathophysiology - LPAR6 is part of a lipid-signaling pathway in epithelial cells of hair follicles, regulating hair shaft growth and structural integrity. The mutation causes loss or reduction of receptor function, disrupting this signaling, leading to weak, woolly, and curly hair shafts with lack of guard hairs. This results in the Cornish Rex’s distinctive soft, wavy “rexoid” coat and characteristic bent whiskers. The phenotype is fixed in the breed.
Complications - The curly coat itself does not cause health problems but requires special grooming care. Cornish Rex cats lack the typical resilient guard hairs, making their coats softer and more delicate. Bent and twisted whiskers are often present with the mutation. No systemic or fatal complications are linked directly to this genetic variant or coat type.
Why This Matters to Breeders and Vets - Breeders use genetic testing for the LPAR6 mutation to confirm breed purity and manage matings to produce or maintain the Cornish Rex curly coat trait. Knowing carrier status helps avoid unexpected coat phenotypes in offspring. Veterinarians benefit from understanding this mutation when diagnosing coat phenotypes or advising owners on grooming and care of curly-coated Cornish Rex cats. The genetic test assists in breed standard maintenance and overall breed health monitoring.
Summary - The Cornish Rex curly coat is caused by a pathogenic autosomal recessive mutation in the LPAR6 gene, resulting in loss of receptor function critical for hair follicle integrity. The phenotype features soft, wavy, curl-patterned fur and bent whiskers. This mutation is fixed in the breed, with carriers showing normal coats. Genetic testing is established and important for confirming the curly coat genotype, supporting breeding and breed management decisions. The coat mutation itself is cosmetic and not associated with health problems.
