Cerebral dysgenesis

Gene: PEA15

Transmission: Autosomal recessive

For an autosomal recessive genetic disease, an animal must have two copies of the mutation in question to be at risk of developing the disease.  Both parents of an affected animal must be carriers of at least one copy of the mutation.  Animals that have only one copy of the mutation are not at risk of developing the disease but are carrier animals that can pass the mutation on to future generations.

Mutation: Deletion, PEA15 gene; c.176 del. A, p.(Asn59 fs), exon2, chr.F1.

Medical system: Neurological

Breeds: Domestic Cat

Age of onset of symptoms: By 3 – 4 weeks

The PEA15 gene plays an important role in brain development.  A mutation identified in the cat PEA15 gene is responsible for a phenotype of microcephaly and polymicrogyria of the brain.  Clinical signs, evident from 3 to 4 weeks after birth, include a hypermetric gait, tremors, and dissociative behavior.  Signs are not progressive and stabilize within 6 to 9 months.  By one year of age, sensory abnormalities and aggression can be seen. Epileptic seizures may also be a feature.

The mutation in the PEA15 gene occurred naturally within a research colony of domestic cats but has not entered the general cat population.  Thus, the mutation and the cerebral dysgenesis phenotype that it causes are of academic interest but are not of practical concern to cat breeders.

References:

OMIA link: [2303-9685]

Graff EC, Cochran JN, Kaelin CB, et al. (2020) PEA15 loss of function and defective cerebral development in the domestic cat. PLoS Genet 16:e1008671.  [pm/33290415]

Contributed by: Angélika Racicot et Mégane Plourde, Class of 2028, Faculty of Veterinary Medicine, University of Montreal. (Translation DWS).