Definition:

Tay-Sachs disease is an autosomal recessive lysosomal storage disorder caused by mutations in HEXA that encodes beta hexosaminidase subunit alpha. In the absence of hexosaminidase A, GM2 ganglioside cannot be hydrolyzed and therefore accumulates primarily in neuronal tissues. This results in progressive neurologic degeneration. Patients with infantile Tay-Sachs disease die before the age of five, whereas patients with the juvenile and adult forms have a delayed onset.