Lysosomal storage diseases (
LSDs; ) are a group of approximately 50 rare inherited
metabolic disorders that result from defects in
lysosomal function.
Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling. This process requires several critical enzymes. If one of these enzymes is defective, because of a mutation, the large molecules accumulate within the cell, eventually killing it.