CEREBRAL LIPIDS IN A CASE OF SYSTEMIC GM2-GANGLIOSIDOSIS OF A LATE INFANTILE TYPE1

—Quantitative analyses performed on the lipids of cerebral grey matter from brains of a normal child and a child with Tay-Sachs (T-S) disease were compared with such analyses on the brain of a 6-year-old, non-Jewish male with systemic G_M2-gangliosidosis of a late infantile type (G_M2-LI). Analysis of gangliosides showed a 3·5-fold increase of total gangliosides in the G_M2-LI brain and a six-fold increase in the T-S brain, compared to normal brain. Both pathological brains had similar distribution patterns for gangliosides, with the G_M2-ganglioside component constituting more than 80 per cent of the total. Lipid components in the T-S brain were below normal values except for lecithin and cholesterol, while in the G_M2-LI brain there were increases in sulphatides, cerebrosides, sphingomyelin and cholesterol. Approximately twice as much ceramide trihexoside was present in the T-S brain as in the G_M2-LI brain, and none could be detected in the normal brain. The clinical, pathological and biochemical data support the conclusion that this case represents a new variant of systemic late-infantile gangliosidosis in which there is an accumulation of the G_M2-ganglioside like that in Tay-Sachs disease.