ARSB (Arylsulfatase B) is an enzyme responsible for breaking down certain glycosaminoglycans, particularly dermatan sulphate. Proper ARSB activity helps prevent the build-up of these molecules in tissues. Deficiency or mutations in ARSB lead to Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome), a condition characterised by skeletal abnormalities, organ involvement, and other systemic effects from dermatan sulphate accumulation.