Deaf White Cat Syndrome

Inherited Sensorineural Deafness Related to Coat Color

History

  • Darwin 1859. Released information that made it known that deafness and eye color is genetically controlled
  • Bergsma and Brown, published by the Journal of Heredity in 1971. Theories about deaf white cat syndrome associated with blue eyes, head markings in kittens, and carriers of the white spotting gene
  • 1999 Feline breeding organizations published ways to avoid breeding offspring with congenital deafness

Description


  • Pigment granule deficiency in the hair and eyes (not albino), coupled with anomalies of the inner ear.
  • Signs of loss of hearing within the first week after birth due to cochleo-saccular degeneration
  • Diagnosis can be accomplished from lack of response to sound
  • Congenital sensorineural (neural crest of the hearing pathway is affected) related to coat color or coat pattern
  • Has been diagnosed within species besides the cat: dogs, horses, llamas, alpacas
  • Related to the absence of melanocytes within the inner ear (region of the cochlea known as the stria vascularis).
  • No treatment for deaf white cat syndrome
  • Linked to Waardenburg Syndrome in humans

Why It's a Problem/Important

  1. Cats with defects are less likely to be adopted
  2. Cats born deaf in the wild have a decreased chance of living
  3. It's linked to syndromes within other animals (including humans). Finding a solution to this syndrome could help more than one species.

Genetic Information

  • Autosomal Dominant
  • Not sex linked
  • Genotype - dominant gene W ("white" gene is coincidental) refers to the inheritance of the anomaly of the neural crest that leads to degeneration into deafness
  • Blue eyes and blindness found in only a proportion of those with the dominant white allele
  • "white" gene is present in 14 registered breeds
  • Example of matings of two dominant white cats resulted in 89.3%, 95.8% and 52.0% cats, respectively, with impaired hearing
  • Example of matings between white cats and cats with a pigmented coat led to a prevalence of 24.6–27.4% of individuals with impaired hearing.

  • Polygenic trait --> inherent with all cats with the gene

Phenotypes

Biological Differences

Ages of Progression

Likelihood of Inheritance

  • White cat with orange eyes - decreased (~17% and 22%)
  • White cat with blue eyes - increased (~85% and 65%)
  • White cat that is born with a patch of color that disappears in adulthood - decreases
  • White cat with one blue eye - decreased (~40% and 39%)
  • Pure bred white cats - decreased compared to cross-bred cats
  • Long haired white cats - increased compared to short haired white cats

Selective Breeding

Breeding against the syndrome would be very difficult, if not impossible. In order to accomplish this, the degree of severity of the neural crest anomaly needs to be understood. Only matings between white coated orange eyed cats with hearing could be allowed because they can hear despite the white coat. The cats born with the colored patch increases favorability. Blue eyed and deaf cats would have to be removed from breeding because they will 100% give birth to babies with the syndrome. Interbreeding between different color coated cats can't be allowed because the state of the neural crest is unknown. Results would could breed kittens with the syndrome in further generations.

Eradication Barriers

  1. Difficulty in making selective breeding widespread
  2. Lack of research on the subject
  3. Ability to figure out the degree of severity of the anomaly within different white coated cats
  4. The inability to figure out the degree of of the anomaly within regular cats
  5. The inability to detect the exact marker that causes the syndrome

Opinion

Personally, I think they're fine as they are. Animals are good at adapting to their situations, and since these cats are born deaf they can adjust from the beginning. The syndrome could lead to less adoption, or lesser chance of survival in the wild. However, people like cats that are white with blue eyes. They make pretty pets and would be adopted none-the-less. Besides the fact that they're deaf, fertility is fine and they don't suffer. There isn't much research or information on this syndrome. The only reason some people tried to look into this, is to see if this syndrome could relate to human diseases. In which case, they could figure out if the syndrome could be fixed in cats at a young age and apply it to humans. What do you think? Should more research be done? Are they fine as they are?

Citation

  • Brinicombe, David. "The 1995 All Breed White Deafness Survey." Keoka Maine Coons. N.p., 25 Sept. 1995. Web. 01 May 2015. <http://www.keoka.com/whtdeaf/index.htm>.
  • Geigy, Caroline A, et al. "Does a Pleiotropic Gene Explain Deafness and Blue Irises in White Cats?" The Veterinary Journal 173 (2003): 548-553. Web. 01 May 2015. <http%3A%2F%2Fac.els-cdn.com.ezproxy.proxy.library.oregonstate.edu%2FS1090023306001699%2F1-s2.0-S1090023306001699-main.pdf%3F_tid%3D5c1842ae-f384-11e4-9a5f-00000aacb360%26acdnat%3D1430871233_2f9d8b43f92cd0a8e59dc1010fa33758>.
  • Robinson, Roy. "White Cats and Deafness." Cats, U.K. (n.d.): n. pag. 18 Aug. 1995. Web. 1 May 2015. <http://www.weisszucht.de/pdf/WhiteCatsandDeafnessbyRoyRobinson.pdf>
  • Ryugo, David K., et al. "Separate Forms of Pathology in the Cochlea of Congenitally Deaf White Cats." Hearing Research 181 (2003): 73-84. Web. 01 May 2015. <http://ac.els-cdn.com.ezproxy.proxy.library.oregonstate.edu/S0378595503001710/1-s2.0-S0378595503001710-main.pdf?_tid=6fac6552-f384-11e4-82a2-00000aacb35d&acdnat=1430871266_e7733ca200f0032ac0d246d0ea6bdf31>.
  • Saada, Ahmed A., John K. Niparko, and David K. Ryugo. "Morphological Changes in the Cochlear Nucleus of Congenitally Deaf White Cats." Brian Research 736 (1996): 315-328. Web. 01 May 2015. <http%3A%2F%2Fac.els-cdn.com.ezproxy.proxy.library.oregonstate.edu%2F0006899396007196%2F1-s2.0-0006899396007196-main.pdf%3F_tid%3D9ef40eb6-f382-11e4-9115-00000aacb35e%26acdnat%3D1430870486_b0664fcae872a6fcbc4e9c465adc7471>.
  • Webb, Aubrey A., and Cheryl L. Cullen. “Coat Color and Coat Color Pattern-Related Neurologic and Neuro-Ophthalmic Diseases.” The Canadian Veterinary Journal 51.6 (2010): 653–657. Print.