Categories: Integument (skin) phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 615895 (trait) , 608245 (gene)

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal incomplete dominant

Disease-related: no

Key variant known: yes

Year key variant first reported: 2013

Species-specific name: Selkirk autosomal dominant Rex

Species-specific symbol: SADRE; Re^S

History: The Selkirk Rex is a relatively new breed of curly-coated cat that is based on a spontaneous mutation that was discovered in the USA in 1987 (Filler et al., 2012).

Inheritance: Filler et al. (2012) provided a genetic analysis of the Selkirk Rex breed, reporting "incomplete dominant expression of the curly trait in the Selkirk Rex" and noting that "Homozygous curl cats can be distinguished from heterozygous cats by head and body type, as well as the presentation of the hair curl."

Mapping: By conducting a GWAS on 9 curly-coated Selkirk Rex and 29 control cats (comprising 6 Selkirk Rex straight-haired, 5 Persians, and 18 Scottish Folds), each genotyped with the Illumina Infinium Feline 63 K iSelect SNP chip (yielding 52,553 informative SNPs), Gandolfi et al. (2013) mapped the curly-coat trait to a 716kb region on cat chromosome B4, namely from 81,264,280 to 81,980,475. A ~600kb haplotype within this region was shown (from the feline-human comparative map) to contain 26 (candidate) keratin genes.

Molecular basis: By sequencing some of the comparative positional candidate keratin genes described in the Mapping section, Gandolfi et al. (2013) identified the causal mutation as a c.445-1G>C SNP which "likely disrupts the highly conserved acceptor splicing site of intron one." They also reported that "Sequence of the complete RNA transcript revealed that an alternative downstream acceptor was employed. The new alternative acceptor site was found within the first 18 bp of exon 2 (r.445_464del), thus an alternative splice site was recognized at base 18 in the modified exon 2. In silico translation predicted the loss of 6 amino acids in the KRT71 protein."

Breed: Selkirk Rex (Cat) (VBO_0100215).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).

Associated gene: