Spinal Muscular Atrophy

 

Gene: LIX1

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, LIX1 gene; del. 140kb

Breeds: Highland Lynx, Maine Coon

Medical Systems: Muscular, neurological, neuromuscular

Age of onset of symptoms:  By 3 to 4 months of age

Spinal muscular atrophy is a genetic disorder that is specific to the Maine Coon cat.  This neurological disease is characterized by loss of lower motor neurons leading to muscle denervation, muscle atrophy, weakness and tremors.  Typically, by 3 to 4 months of age an affected animal begins to show clinical signs such as unsteadiness in the hind limbs.  The severity and progression of spinal muscular atrophy is variable, and the disease can progress over several years.

 

References:

OMIA link: [2389-9685]

Anderson H, Davison S, Lytle KM, et al. (2022) Genetic epidemiology of blood type, disease and trait variants, and genome-wide genetic diversity in over 11,000 domestic cats.  PLoS Genet. 16;18(6):e1009804.  [pubmed/35709088]

Wakeling EN, Joussemet B, Costiou P, et al. (2011) Failure of lower motor neuron radial outgrowth precedes retrograde degeneration in a feline model of SMA. J Comp Neurol 520:1737-1750. [pubmed/22120001]

Fyfe JC, Menotti-Raymond M, David VA, et al. (2006) An approximately 140-kb deletion associated with feline spinal muscular atrophy implies an essential LIX1 function for motor neuron survival. Genome Res. 16(9):1084-1090. [pubmed/16899656]