Mucopolysaccharidosis type VI (MPS VI, Maroteaux-Lamy syndrome, polydystrophic dwarfism; MIM:253200) is an autosomal recessive lysosomal storage disorder caused by a deficiency in arylsulfatase B (ARSB, N-acetyl-galactosamine 4-sulfatase; MIM:611542). It is named after two French physicians, Pierre Maroteaux and Maurice Emil Joseph Lamy. Maroteaux first described this disorder as a novel dysostosis associated with increased urinary excretion of chondroitin sulfate (CS; Maroteaux et al. 1963). The gene encoding ARSB is mapped to chromosome 5q11-q13 (Fidzianska et al. 1984) and contains 8 exons spanning about 206 kb (Karangeorgos et al. 2007). Defective ARSB results in build up of dermatan sulfate (DS) and chondroitin sulfate (CS) in soft tissues causing compression and blockages in blood vessels, nerves, trachea, corneal clouding and disrupting normal bone development. Symptoms are similar to MPS I but with normal intelligence generally (Rapini et al. 2007, Valayannopoulos et al. 2010).