While looking into MPS, we found that all MPS I patients had pathogenic mutations in the IDUA gene, mutations in the SGSH gene in MPS IIIA, mutations in the NAGLU, GNPTAB, and HFE genes in MPS IIIB, and mutations in the GALNS gene in MPS IV. This evidence concerns the gene GNPTAB and mucopolysaccharidosis type 3B.