1 Department of Pediatrics, Case Western Reserve University School of Medicine at the Cleveland Metropolitan General Hospital, Cleveland, Ohio
GM1 generalized gangliosidosis is an autosomal recessive inherited disease, characterized by the storage of GM1 ganglioside in brain and visceral tissues secondary to a deficiency of the enzyme
-galactosidase. The enzyme deficiency found in brain, liver, and cultured flbroblasts is also present in the leukocyte. Using leukocytes as the test tissue two GM1 gangliosidosis putients were clearly identified from patients with clinically similar storage diseases. The enzyme activity in obligate heterozygotes showed intermediate levels between their affected children and normal controls, suggesting that heterozygotes may be identified using the leukocyte as the test tissue.