Arylsulfatase is an enzyme that breaks down specific lipids called sulfate esters. There are two main types of arylsulfatase: A and B. Deficiency
in arylsulfatase A (ASA) is a condition known as metachromatic leukodystrophy, while arylsulfatase B deficiency is indicative of Maroteaux-Lamy syndrome or polydystrophic dwarfism
. Metachromatic leukodystrophy is a hereditary disease in which sulfate esters accumulate primarily in the nervous system, which causes neurological disorders from the age of 2 affecting walking ability and causing cognitive
deterioration followed by death in just a few years.