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All Diseases > Hunter Syndrome
Hunter Syndrome (MPS II)
Alternative Names: Mucopolysaccharidosis Type II; Iduronate 2-Sulfatase Deficiency (I2S Deficiency)
Disease Category: Lysosomal Diseases
A rare, X-linked recessive (requiring two gene mutations found on the X chromosome - one from each parent), inherited, lysosomal disorder, caused by a missing or abnormal enzyme which cannot break down glycosaminoglycans (GAGs, complex sugar molecules with amino groups that are critical components of connective tissues). The 2 subtypes, non-neuronopathic (mild form not affecting neurons) and neuronopathic (severe form affecting neurons), manifest in early childhood, affecting the respiratory airway, eyes, ears, liver, spleen, and the skeletal, neurological, and cardiac systems.