These are a group of inherited diseases that are often manifested in childhood due to deficiency of sphingolipid degrading enzymes (in lysosomes) .
all are autosomal recessive disorders except Fabry disease (X-linked)
(1) Complex lipids containing ceramide accumulate in cells, particularly neurons, causing neurodegeneration and shortening the life span.
(2) The rate of synthesis of the stored lipid is normal.
(3) The enzymatic defect is in the lysosomal degradation pathway of sphingolipids.