Retinal degeneration in the Abyssinian and Somali cat (rdAc): correlation between genotype and phenotype and rdAc allele frequency in two continents.

Objective: To characterize hereditary retinal degeneration in the Abyssinian cat (rdAc) in a recently established closed colony segregating for the rdAc mutation, and evaluate possible differences in the age of onset and progression of disease phenotype since the initial description of rdAc 25 years ago. The sample size of an earlier study was increased in order to determine the allele frequency in Abyssinian and Somali cats on a worldwide basis.

Animals Studied: Twenty rdAc affected cats from the closed animal facility, 87 Abyssinian and Somali cats for study of genotype-phenotype concordance, and DNA from 131 Abyssinian and Somali cats from Scandinavia, the UK and Australia for evaluation of the rdAc allele frequency.