In an inherited metabolic disorder known as MPS IIIA the lysosomal exo-enzyme, N-sulfoglucosamine sulfohydrolase (SGSH; EC 3.10.1.1), responsible for cleaving sulfate from non-reducing end glucosamine N-sulfate (GlcNS) residues in HS is deficient. The gene discussed is SGSH; the disease is Other metabolic disease.