Korat GM2 Gangliosidosis

Quick Summary

Korat GM2 gangliosidosis causes progressive neurologic dysfunction and premature death in Korat cats. Disease progression is more rapid in GM2 than GM1.

Phenotype: Korat GM2 gangliosidosis causes progressive neurologic dysfunction and premature death in Korat cats. Disease onset is observed as early as 4 weeks of age, beginning with fine head tremors, followed rapidly by ataxia, and progresses to death before 8 months of age.

Mode of Inheritance: Autosomal recessive

Alleles: N = Normal, GM2k = Korat GM2 gangliosidosis

Breeds appropriate for testing: Korat

Explanation of Results:

  • Cats with N/N genotype will not have Korat GM2 gangliosidosis and cannot transmit this GM2 variant to their offspring.
  • Cats with N/GM2k genotype will not have Korat GM2 gangliosidosis, but are carriers. They will transmit this GM2 variant to 50% of their offspring. Matings between two carriers are predicted to produce 25% kittens with Korat GM2 gangliosidosis.
  • Cats with GM2k/GM2k genotype will have Korat GM2 gangliosidosis, a fatal condition.
Price

$40 one test per animal
$65 this test + Korat GM1 per animal

Additional Details

Gangliosidoses are degenerative, fatal neurological diseases caused by abnormal accumulation of lipids known as gangliosides in central and peripheral nervous systems, and nerve cells in particular. Cats affected with gangliosidosis have progressive neurologic dysfunction and premature death. Two forms of gangliosidosis affect Korat cats – GM1 and GM2. Both have a genetic basis and a recessive mode of inheritance. Two copies of the defective gene are needed to cause the disease. Both diseases cause similar progressive neurologic dysfunction, including tremors, ataxia and dysmetria. Disease progression is more rapid in GM2.

Korat GM2 is caused by a mutation in the feline Hexoaminidase β-subunit (HEXB) gene. Disease onset is observed as early as 4 weeks of age, beginning with fine head tremors, followed rapidly by ataxia, and progresses to death before 8 months of age.

Testing for GM1 and GM2 in Korat cats to assists owners and breeders in identifying affected and carrier cats. Breeders can use these tests as a tool to avoid breeding carriers together which would produce 25% affected offspring.

 

Note: This test is specific for the 1 base deletion in the HEXB gene that causes GM2 in Korat cats. It will not detect other HEXB mutations known to exist in other breeds of cats.
Turnaround Time
2-6 business days
Type of Sample

Species

Cat

Breed

Type of Test

Results Reported As
Test Result GM2 Gangliosidosis Status
N/N Normal. Cat does not have GM2 Korat mutation.
N/GM2k Carrier. Cat has one copy of GM2 Korat mutation. Breedings between carriers will be expected to produce 25% affected kittens.
GM2k/GM2k Affected.
References

Muldoon, L.L., Neuwelt, E.A. , Pagel, M.A., & Weiss, D.L. (1994). Characterization of the molecular defect in a feline model for type II GM2-gangliosidosis (Sandhoff Disease). American Journal of Pathology, 144,1109-1118.

Baker, H.J., Smith, B.F., Martin, D.R., & Foureman, P. (2001). Molecular Diagnosis of Gangliosidoses: A model for elimination of inherited diseases in pure breeds. Consultations in Feline Internal Medicine 4, J.R. August (ed.). Saunders WB, Philadelphia. pp 615-620.

Martin, D.R., Rigat, B.A., & Foureman, P. (2008). Molecular consequences of the pathogenic mutation in feline GM1 gangliosidosis. Molecular Genetics and Metabolism, 94, 212-221. doi: 10.1016/j.ymgme.2008.02.004