Furthermore, the activity of other LSD enzymes such as iduonate-2-sulfatase for MPS II, N-acetylgalactosamine-6-sulfatase for MPS IVA, N-acetylgalactosamine-4-sulfatase for MPS VI, α-N-acetylglucosainidase for MPS IIIB, and lysosomal β-glucuronidase for MPS VII has been developed [9]. The gene discussed is ARSB; the disease is isovaleric acidemia.