Juvenile GM₁ gangliosidosis: Clinical, pathological, chemical and enzymatic studies

Abstract

Clinical, histological, chemical and enzymatic studies are reported in five patients in two families with juvenile GM 1 gangliosidosis (GM 1 gangliosidosis, Type 2). The clinical picture includes onset of mental and motor retardation beginning at about one year of age and progressive neurological decline with death usually within the first decade. Bony deformities, although mild, are often present and are diagnostically helpful. Ganglioside GM 1 and a galactose‐containing polysaccharide (similar to keratan sulfate) are stored, β‐galactosidase activities are reduced in tissues and cultured skin fibroblasts; both homozygotes and heterozygotes can be detected by this method. The differentiation of juvenile GM 1 gangliosidosis from generalized gangliosidosis (GM 1 gangliosidosis, Type 1) is discussed.