mucopolysaccharidosis type 3C
Findings
No curated finding names mucopolysaccharidosis type 3C yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A rare autosomal recessive lysosomal storage disease caused by deficiency of the enzyme acetyl-CoA:alpha-glucosaminide acetyltransferase. It is characterized by behavioral changes, sleep disturbances, and mental developmental delays.
Definition from the Mondo Disease Ontology (MONDO:0009657), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Juvenile onset · Childhood onset
HPO, annotations 2026-09-02
Features
17 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Coarse facial featuresHPOHP:0000280
- 10 of 11 reported patients
- Intellectual disabilityHPOHP:0001249
- 7 of 11 reported patients
- Hearing impairmentHPOHP:0000365
- 5 of 11 reported patients
- DysphagiaHPOHP:0002015
- 4 of 11 reported patients
- Loss of speechHPOHP:0002371
- 4 of 11 reported patients · Childhood onset
- Global developmental delayHPOHP:0001263
- 3 of 11 reported patients
- HypertrichosisHPO
Show the remaining 5
- HepatomegalyHPOHP:0002240
- 1 of 11 reported patients
- HirsutismHPOHP:0001007
- 1 of 11 reported patients
- SplenomegalyHPOHP:0001744
- 1 of 11 reported patients
- SynophrysHPOHP:0000664
- 1 of 11 reported patients
- Dysostosis multiplexHPOHP:0000943
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- HGSNATHGNC:26527
- Definitive · Ambry Genetics · Autosomal recessive · 2017
- Definitive · ClinGen · Autosomal recessive · 2023
- Definitive · G2P · Autosomal recessive · 2023
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Genomics England PanelApp · Autosomal recessive · 2020
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2019
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
8 names
Resolves to: mucopolysaccharidosis type 3C
- Also called
- heparan-alpha-glucosaminide N-acetyltransferase deficiencyHGSNAT deficiencyMPS III CMPS3CMPSIIICmucopolysaccharidosis type IIICSanfilippo CSanfilippo syndrome type C