Arylsulfatase F, also known as ARSF, is a 590 amino acid secretory protein that belongs to the sulfatase family of bone and cartilage matrix proteins. Arylsulfatase F uses calcium as a cofactor to catalyze reactions that are important in maintaining correct bone composition. The activity of Arylsulfatase F, unlike that of other family members, such as Arylsulfatase E, is not inhibited by warfarin. The gene encoding Arylsulfatase F 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.