An autosomal inherited disease caused by deficiency of the enzymes hexosaminidase A & B (see BETA-N-ACETYLHEXOSAMINIDASE) which leads to an accumulation of GM2 ganglioside and sphingolipid globoside in neurons and other organs. Clinical manifestations resemble TAY-SACHS DISEASE, but the disease is not limited to Askenazi Jews and may feature hepatosplenomegaly. The infantile form presents in the first 4 months of life with psychomotor delay, hypotonia followed by spasticity, and cherry red spots in the macula. Rare juvenile and adult forms have been reported. (From Menkes, Textbook of Child Neurology, 5th ed, p92)