What neurological disorder is characterized by an accumulation of GM2 gangliosides?

Tay Sachs disease is characterized by a deficiency of the enzyme hexosaminidase A, which leads to the accumulation of GM2 gangliosides, particularly in the neurons of the brain. This accumulation is detrimental because GM2 gangliosides are toxic when not properly metabolized. The clinical presentation of Tay Sachs includes developmental regression, loss of motor skills, and characteristic cherry-red spots on the retina. This condition is part of a group of disorders known as GM2 gangliosidoses, which primarily affects infants and young children, leading to neurological decline and early mortality.

In contrast, the other disorders mentioned involve different pathological mechanisms and do not involve GM2 gangliosides. Huntington's disease, for example, is caused by a genetic mutation leading to the production of the huntingtin protein, resulting in neurodegeneration, particularly affecting the basal ganglia. Multiple sclerosis is an autoimmune disorder that affects myelin in the central nervous system, and Alzheimer's disease is associated with the deposition of amyloid plaques and tau tangles in the brain. These distinctions further underscore why Tay Sachs disease specifically correlates with the accumulation of GM2 gangliosides.