Contributor: Gordon K. Klintworth
Most lysosomal storage diseases result from a deficiency of a lysosomal enzyme that is involved in the acid hydrolysis of specific molecules within lysosomes, such as glycosaminoglycans [mucopolysaccharidosis], glycogen [glycogen storage disease], and gangliosides [gangliosidosis]. Cystinosis is an unusual lysosomal storage disease that results not from a lack of a hydrolyic enzyme, but from a deficiency of cystinosin, a protein involved in the transport of cystine across the lysosomal membrane. It is estimated that about 1 in 7,700 children have a lysosomal storage disease.