Breeds Affected: Korat, Siamese, Domestic Short Hair
Samples Accepted: Blood, Buccal Swabs
Disease Information: GM1 Gangliosidosis, a lysosomal storage disorder, is a fatal neuromuscular disease. Affected kittens show head tremors, progressively uncoordinated leg movements and eventually seizures and paralysis. They are usually diagnosed between 3-6 months of age, and rarely live past 1 year of age.
Inheritance Information: GM1 Gangliosidosis is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.
The possible genotypes are:
N/N The cat is normal, and cannot produce affected offspring.
N/gm1 The cat is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/gm1 carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
gm1/gm1 The cat is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/gm1 carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/gm1 x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.
– Breeding two carriers (N/gm1 x N/gm1) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (gm1/gm1) should not be used for breeding.
Test Information: This mutation test identifies a single base change in exon 14 of the GLB1 gene.
Uddin, M.M., Hossain, M.A., Rahman, M.M., Chowdhury, M.A., Tanimoto, T., Yabuki, A., Mizukami, K., Chang, H.S., Yamato, O.: Identification of Bangladeshi domestic cats with GM1 gangliosidosis caused by the c.1448G>C mutation of the feline GLB1 gene: case study. J Vet Med Sci 75:395-7, 2013. Pubmed reference: 23123943.
Martin, DR., Rigat, BA., Foureman, P., Varadarajan, GS., Hwang, M., Krum, BK., Smith, BF., Callahan, JW., Mahuran, DJ., Baker, HJ.: Molecular consequences of the pathogenic mutation in feline GM1 gangliosidosis. Mol Genet Metab 94:212-21, 2008. Pubmed reference: 18353697. Doi: 10.1016/j.ymgme.2008.02.004.
Further information is available at the Online Mendelian Inheritance in Animals website.