Disorder - Gangliosidosis, GM2, GM2A deficiency

Organ Systems Involved
Nervous/sensory

Alternative disorders described within LIDA

Mannosidosis; Mucopolysaccharidosis – Type I, Type II, Type III A, Type III B, Type VI, Type VII; Gangliosidosis – GM1, GM2; Glycogenoses; Ceroid lipofuscinosis; Galactosialidosis; I-cell disease; Sphingomyelinosis aka Niemann-Pick disease

Alternative Names
GM2 gangliosidosis, variant AB

Presenting Signs

Cats with gangliosidosis GM2A deficiency produce insufficient amounts of the GM2 activator protein. This protein is necessary to break down a natural cellular component called GM2 ganglioside. As these cats are unable to break down GM2 ganglioside, it accumulates in their tissues, particularly in the tissues of the nervous system. As a result, the cats show progressive signs of deterioration of the nervous system.

Affected cats begin to show signs of the disease at around 14 months of age. These cats initially show incoordination in their movements, and trembling or shaking (particularly of their heads) that is most obvious when they are intending to move or perform activities such as eating. With progression of disease, their incoordination worsens so that they have difficulty walking. They also become easily startled by loud noises. Late in the disease process, the cats become blind and cannot eat without assistance. They may be observed to have clouded eyes (due to GM2 ganglioside build-up in the corneas). Cats with gangliosidosis GM2A may also suffer from seizures, and show depressed behaviour.

Treatment

None: there is no current treatment for gangliosidosis GM2A deficiency in cats, and it is a progressive disease that eventually necessitates euthanasia for humane reasons.

PubMed References
Gangliosidosis, GM2, GM2A deficiency

Contributor
Holly Boyden