2. Introduction
• Hunter syndrome, or mucopolysaccharidosis type II (MPS II)
• X-linked lysosomal storage disease caused by mutations of the gene encoding the lysosomal enzyme
iduronate-2-sulfatase
• Deficiency of the lysosomal enzyme iduronate-2-sulfatase (I2S) causes accumulation of Large sugar
molecules called glycosaminoglycans (or GAGs or mucopolysaccharides) in body tissues.
GAG 1 GAG 2
GAG 1
GAG 2
Accumulation
of GAG
O linked sulfates
Iduronate-2-sulfatase