Table 1.
Types and initial symptoms of MPSs
| Type | Inheritance | Gene | Deficient enzyme | Stored substrate | Initial symptoms |
|---|---|---|---|---|---|
| I | AR | IDUA | α-L-iduronidase | DS & HS | Skeletal abnormalities (e.g. thoracic deformities, tibial deformities, rapid or delayed growth); hernias; recurrent ear, nose, throat infections; rough facial features; hepatosplenomegaly |
| II | XR | IDS | iduronate-2-sulfatase | DS & HS | Hepatosplenomegaly; heart involvement; rough facial features; chronic respiratory tract infection; noisy and labored breathing; inguinal hernias; chronic/watery diarrhea; skeletal malformations; growth retardation; central nervous system degeneration; developmental and language delays; hearing loss and otitis media |
| IIIA | AR | SGHS | heparan N-sulfatase | HS | Restlessness, destructiveness, anxiousness, and aggressive behavior; hyperactivity and eventually severe dementia; speech delay; recurrent ear, nose, and throat infections; coarse facial features and larger protruding upper lips |
| B | NAGLU | α-N-acetylglucosaminidas | |||
| C | HGSNAT | α-glucosaminidase acetyltransferase | |||
| D | GNS | N-acetylglucosamine-6-sulfatase | |||
| IVA | AR | GALNS | Galactosamine-6-sulfate sulfatase | KS & CS | Pectus carinatum, vertebral body deformities; gibbus deformity; pectus carinatum; short trunk dwarfism; short neck; difficult airway and chronic respiratory infections; cervical spinal cord compression; joint hypermobility; visual dysfunctions; cardiovascular involvement |
| B | GLB1 | β-galactosidase | KS | ||
| VI | AR | ARSB | N-acetylgalactosamine-4sulfatase | DS & CS | Coarse facial features and enlarged tongues; hepatosplenomegaly; short stature; joint stiffness; frequent upper airway infections; spinal cord compression; abnormal gait, cardiovascular disease; reduced pulmonary function |
| VII | AR | GUS | β-glucuronidase | DS、HS & CS | Hydrops fetalis; coarse facial features and large heads with scaphocephaly; progressive degeneration of development; recurrent ear infections; poor vision and hearing; sleep apnea; breathing difficulties, chronic upper respiratory tract infections; rigid chests |
| IX | AR | HYAL1 | hyaluronidase-1 | HA | Progressive joint manifestations and chronic inflammation and pain; short stature; flattened nose; cleft palate |
| X | AR | ARSK | arylsulfatase K | DS | Short stature; facial features and dysostosis multiplex |
Mucopolysaccharidoses (MPS); autosomal recessive (AR); X-linked recessive (XR); chondroitin sulfate (CS); dermatan sulfate (DS); heparan sulfate (HS); hyaluronic acid or hyaluronan (HA); keratan sulfate (KS)