What enzyme is deficient in GM2 gangliosidosis/Tay-Sachs disease?

GM2 gangliosidosis, commonly known as Tay-Sachs disease, is caused by a deficiency in the enzyme hexosaminidase A. This enzyme is vital for the breakdown of GM2 gangliosides, which are complex lipids found in the nerve cells of the brain and spinal cord. When hexosaminidase A is deficient, GM2 gangliosides accumulate, particularly in the neurons, leading to the progressive neurodegeneration characteristic of Tay-Sachs disease.

The buildup of GM2 gangliosides interferes with normal cellular function, resulting in symptoms such as developmental delay, loss of motor skills, and, ultimately, severe neurological impairment. The condition is inherited in an autosomal recessive pattern, meaning that both copies of the gene for hexosaminidase A must be mutated for the disease to manifest.

The other enzymes listed are not involved in GM2 gangliosidosis. Ceramidase is associated with the metabolism of ceramide, glucocerebrosidase is involved in the breakdown of glucocerebroside linked to Gaucher's disease, and sphingomyelinase plays a role in sphingomyelin metabolism, which is related to Niemann-Pick disease. Understanding the specific biochemical pathways affected by