Sulfatases hydrolyze sulfate esters from sulfated steroids, carbohydrates, proteoglycans and glycolipids. They are involved in hormone biosynthesis, modulation of cell signaling and degradation of macromolecules. Arylsulfatase H, also known as ARSH, is a 562 amino acid protein that belongs to the sulfatase family of bone and cartilage matrix proteins. Localized to the plasma membrane, Arylsulfatase H uses calcium as a cofactor to hydrolyze sulfate esters. The gene encoding Arylsulfatase D maps to human chromosome X, which contains nearly 153 million base pairs and houses over 1,000 genes. In conjunction with chromosome Y, chromosome X is responsible for sex determination. There are a number of conditions related to an abnormal number and combination of sex chromosomes, some of which include Turner's syndrome, color blindness, hemophilia and Duchenne muscular dystrophy.