Cat Breeds With Congenital Deafness
Very little information is available documenting deafness in various
cat breeds. Deafness can result from effects of the dominant white (W) gene.
A dominant piebald or white-spotting gene (S) is also found in various cat
breeds (Pedersen, 1991; Searle, 1968), but there has been no report of deafness
associated with its presence. Cats carrying the W gene are not always solid
white, often having colored spots on their heads that may disappear with
age. Unlike dogs with the merle gene, homozygous white cats do not have
visual or reproductive defects, but they are more prone to the occurrence
of blue irises and deafness, either unilateral or bilateral, and deafness
occurrence increases with the number of blue eyes (Delack, 1984). Long-haired
cats have a higher prevalence of blue eyes and deafness than short-haired
cats (Mair, 1973). White cats carrying the underlying cs Siamese dilution
pigment gene can have blue eyes without deafness, and it has been suggested
that the presence of this gene explains why purebred white cats are less
often deaf than mixed-breed white cats (Pedersen, 1991). Data supporting
this is not available.
From studies of mixed-breed white cats (the W gene):
- Out of 256 white cats from three studies (Bosher & Hallpike, 1965;
Mair, 1973; Bergsma & Brown, 1971; reviewed by Delack, 1984), 12.1%
were unilaterally deaf and 37.9% were bilaterally deaf, or a total of
50% were affected (Delack, 1984).
- When cats that were the offspring of two white parents were examined,
the prevalence of deafness (unilateral or bilateral) ranged from 52% to
- When Mair (1973) and Bergsma & Brown (1971) examined the effect
of blue eye color on deafness, they found, respectively, a prevalence of
deafness (unilateral and bilateral combined) of 85% and 64.9% in cats with
two blue eyes, 40% and 39.1% in cats with one blue eye, and 16.7% and 22%
in cats with no blue eyes.
- Purebred white cats are said to have a lower prevalence of deafness
than mixed-breed white cats (Pedersen, 1991), but supporting data are unavailable.
- I am unaware of any study of deafness in cats by specific breed.
Pure cat breeds carrying the white (W) coat pigment gene (Gebhard
et al., 1979) and at risk for congenital deafness (no prevalence data available):
- White Scottish Fold
- European White
- Foreign White
- Norwegian Forest Cats
- White Turkish Angora
- White American Wirehair
- White Cornish Rex
- White American Shorthair
- White Devon Rex
- White British Shorthair
- White Manx
- White Exotic Shorthair
- White Persian
- White Oriental Shorthair
- White Maine Coon
It is obvious that much more research needs to be performed before deafness
in cats is well understood. I would welcome further information from those
who may be aware of resources I have not discovered. If you know of a
cat breed with pigment-associated congenital deafness that is not listed
here, please let me know at: firstname.lastname@example.org.
References (see also Bibliography
of Publications Related to Deafness in Cats):
- Bergsma, D.R. & Brown, K.S. (1971). White fur, blue eyes, and deafness
in the domestic cat. Journal of Heredity 62, 171-185.
- Bosher, S.K. & Hallpike, C.S. (1965). Observations of the histological
features, development and pathogenesis of the inner ear degeneration of
the deaf white cat. Proceedings of the Royal Society of London B
- Delack, J.B. (1984). Hereditary deafness in the white cat. Compendium
on Continuing Education for the Practicing Veterinarian 6,609-619.
- Gebhardt, R.H., Pond, G. & Raleigh, I. (1979). A Standard Guide
to Cat Breeds. New York: McGraw-Hill Book Co.
- Mair, I.W.S. (1973). Hereditary deafness in the white cat. Acta
Otolaryngologica Suppl 314,1-48.
- Pedersen, N.C. (1991). Feline Husbandry. Goleta, CA: American
- Searle, A.G. (1968). Comparative Genetics of Coat Colour in Mammals.
London: Logos Press.
Dr. George M. Strain
Louisiana State University
Comparative Biomedical Sciences
School of Veterinary Medicine
Baton Rouge, Louisiana 70803
November 5, 2009
to Deafness in Dogs & Cats