IEMbase 0247: GALNS-related N-Acetylgalactosamine 6-sulfatase deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 247 |
| Nosology | 20.2.07.01 |
| Gene | GALNS |
| External IDs | OMIM:253000; ORPHA:309297 |
| Generated mapping | MAPPED; Morquio_syndrome.yaml#Type A |
| Candidate DisMech targets | Morquio_syndrome.yaml#Type A |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents this as GALNS-related N-acetylgalactosamine 6-sulfatase deficiency, with alternate labels Morquio A disease, mucopolysaccharidosis type 4A, and MPS IVA. The record is autosomal recessive and treatability is marked unknown, with no treatment rows in the cached JSON.
Biochemical rows include decreased N-acetylgalactosamine-6-sulfatase activity in white blood cells, urinary chondroitin sulfate that ranges from normal to increased by age, urinary keratan sulfate that ranges from normal to increased, and total urinary glycosaminoglycans that range from normal to increased. Clinical rows include Alder-Reilly anomaly, cervical myelopathy, coarse facial features, dental spacing, joint laxity, liver dysfunction, peg-shaped incisors, restrictive lung disease, tooth surface loss, and valvular thickening. Characteristic rows include atlanto-axial instability, corneal clouding, degenerative hip dysplasia, dysostosis multiplex, genu valgum, hearing loss, kyphosis, odontoid hypoplasia, short stature, and sternal bulging.
DisMech phenotype coverage
Morquio_syndrome.yaml#Type A is the correct local target. The local file
covers MPS IV as an autosomal recessive glycosaminoglycan degradation disorder,
with Type A defined by GALNS/N-acetylgalactosamine-6-sulfatase deficiency and
keratan plus chondroitin-6-sulfate storage. DisMech captures skeletal dysplasia,
joint laxity, odontoid hypoplasia, cervical cord compression, airway disease,
corneal clouding, hearing loss, cardiac valve disease, usually preserved
intelligence, enzyme and urinary GAG testing, molecular confirmation, Type A
elosulfase alfa therapy, and orthopedic, airway, and supportive management.
Concordance and completeness
Judgement: correct subtype-level mapping with high concordance.
IEMbase and DisMech agree on the GALNS/MPS IVA identity, enzyme deficiency, keratan and chondroitin sulfate storage, urinary GAG signal, skeletal dysplasia, atlanto-axial and odontoid/cervical disease, corneal clouding, hearing loss, short stature, airway/lung disease, and valvular involvement. IEMbase adds a compact checklist for dental findings, liver dysfunction, restrictive lung disease, genu valgum, and age-dependent urinary GAG interpretation.
Curation actions
- Keep this record mapped to
Morquio_syndrome.yaml#Type A. - No mapping correction is needed.
- Use IEMbase's dental, hip, lung, liver, and age-dependent biomarker rows as enrichment prompts during future Morquio syndrome review.