Lipid Storage Disorders: Background, Pathophysiology, Mode of Inheritance Share Feedback Background Lipid storage disorders are a family of diverse diseases related by their molecular pathology. In each disorder, a deficiency of a lysosomal hydrolase is inherited, which leads to lysosomal accumulation of the enzyme's specific sphingolipid substrate. [1, 2] Lipid substrates share a common structure, including a ceramide backbone (2-N-acyl-sphingosine), in which various sphingolipids are derived by substitution of hexoses, phosphorylcholine, or one or more sialic acid residues on terminal hydroxyl groups of the ceramide molecule. Pathways of glycosphingolipid metabolism in both nervous tissue and visceral organs are elucidated, and for each catabolic step, a genetically determined metabolic derangement is identified. [3] Examples of lipid storage disorders include GM1 gangliosidoses, [4] GM2 gangliosidoses, [4] Gaucher disease, sphingomyelinase deficiency or Niemann-Pick disease (NPD...