Iduronate 2-sulfatase is a sulfatase enzyme that catalyze the hydrolysis of sulfate ester bonds from a wide variety of substrates, including steroids, carbohydrates and proteins. Iduronate 2-sulfatase is required for the lysosomal degradation of heparan sulfate and dermatan sulfate. Mutations in the iduronate 2-sulfatase gene that result in enzymatic deficiency lead to the sex-linked mucopolysaccharidosis type II, also known as Hunter syndrome.