HEXB
Chr 5ARhexosaminidase subunit beta
Also known as: ENC-1AS, HEL-248, HEL-S-111
Hexosaminidase B encodes the beta subunit of lysosomal beta-hexosaminidase, which degrades GM2 ganglioside and other molecules containing terminal N-acetyl hexosamines. Mutations cause Sandhoff disease (GM2-gangliosidosis type II) with infantile, juvenile, and adult forms through autosomal recessive inheritance. The pathogenic mechanism involves accumulation of GM2 ganglioside in neurons leading to neurodegeneration.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Mild missense constraint
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
HEXB · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
External Resources
Links to major genomics databases and tools