An autosomal recessive disorder caused by a deficiency of acid beta-glucosidase (glucosylceramidase) leading to intralysosomal accumulation of glycosylceramide mainly in cells of the mononuclear phagocyte system. The characteristic Gaucher cells, glycosphingolipid-filled histiocytes, displace normal cells in bone marrow and visceral organs causing skeletal deterioration, hepatosplenomegaly, and organ dysfunction. There are several subtypes based on the presence and severity of neurological involvement.