There is a lack of hexosaminidase A, which results in an accumulation of GM2 Ganglioside - in the heart. Neurons are balloned with cytoplasmic vacuoles 4401 each of which is a lysosome distended with gangliosides. EM shows whorled cytoplasmic inclusions within lysosomes 4102 . Clinically, there is progressive dementia, motor incordination with muscular flaccidity, and blindness. Death occurs by age 2 0r 3.
Antenatal diagnosis is possible by fibroblast culture from amniotic fluid.
There is a deficiency of aryl-sulfatase A, leading to accumulation of galactosyl sulfatide. Although there is extensive cerebral demyelination, there is characteristic sparing of the subcortical white matter. Sex linked recessive. There are large plaques of demyelination in the cerebral hemispheres, and all patients have adrenal insufficiency. On EM, diagnostic cleft-like intracytoplasmic inclusions are found in CNS macrophages, adrenal cortical cells, and Schwann cells.