mucopolysaccharidosis type 3B
Findings
No curated finding names mucopolysaccharidosis type 3B 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 N-acetyl-alpha-D-glucosaminidase. It is characterized by behavioral changes, sleep disturbances, and mental developmental delays.
Definition from the Mondo Disease Ontology (MONDO:0009656), 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
3 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.
- Dysostosis multiplexHPOHP:0000943
- 16 of 16 reported patients
- Intellectual disabilityHPOHP:0001249
- 16 of 16 reported patients
- Reduced tissue alpha-N-acetylglucosaminidase activityHPOHP:6000360
- 7 of 7 reported patients
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.
- NAGLUHGNC:7632
- Definitive · ClinGen · Autosomal recessive · 2022
- Definitive · Myriad Women's Health · Autosomal recessive · 2018
- Definitive · G2P · Autosomal recessive · 2023
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Genomics England PanelApp · Autosomal recessive · 2020
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2022
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
8 names
Resolves to: mucopolysaccharidosis type 3B
- Also called
- MPS III BMPS3BMPSIIIBmucopolysaccharidosis type IIIBN-acetyl-alpha-glucosaminidase deficiencySanfilippo BSanfilippo syndrome BSanfilippo syndrome type B