All three Gaucher variants are inherited "storage" diseases. They result from the deficiency of an enzyme, acid beta-glucosidase, that is necessary for the breakdown of a particular fatty substance, glucosyl ceramide. Normally, glucosyl ceramide is present in very small amounts in all body cells where it is produced, broken down, and then re-synthesized daily, allowing for the normal growth of cells. In Gaucher patients, glucosyl ceramide cannot be broken down properly. It therefore becomes abnormally stored in those cells normally assigned to metabolize this substance. These enlarged, abnormal cells are known as Gaucher cells.
The major manifestations of Gaucher disease are the result of the abnormal accumulation of Gaucher cells, primarily, in the bone marrow, spleen and liver. Only in patients with Types II and III Gaucher disease does the accumulation also occur in the central nervous system.