Mutations in the GM2A gene cause<unk> . This condition is inherited in an autosomal recessive pattern. The GM2A gene provides instructions for making a protein called the GM2 activator. This protein is required for the normal function of beta-hexosaminidase A, a critical enzyme in the nervous system that breaks down a lipid called GM2 ganglioside. If mutations in both alleles at this locus disrupt the activity of the GM2 activator, beta-hexosaminidase A cannot perform its normal function. As a result, gangliosides accumulate in the central nervous system until they interfere with normal biological processes. Progressive damage caused by buildup of gangliosides leads to the destruction of nerve cells.<unk>  is extremely rare. In contrast with both Tay–Sachs disease and Sandhoff disease, in which many mutant polymorphic alleles have been discovered, including pseudodeficiency alleles, very few GM2A mutations have been reported. When<unk><unk>  is reported, in often occurs with consanguineous parents or in genetically isolated populations. GM2A is expressed in many tissues, and the GM2 activator protein has been reported to have other cellular functions. Because<unk><unk>  is so rarely diagnosed, it is likely that most mutations of GM2A are fatal at the embryonic or fetal stage of development in homozygotes and genetic compounds, and thus are never observed clinically.
GM2-gangliosidosis, AB variant
GM1 gangliosidoses
GM2 gangliosidoses
Adult polyglucosan body disease
Mucopolysaccharidosis type I
Glycogen storage disease type 0
Mucolipidosis type IV
Griscelli syndrome type 2