GLB1

Chr 3AR

galactosidase beta 1

Also known as: EBP, ELNR1, MPS4B

NCBI Gene: 2720ENSG00000170266UniProt: P16278OMIM: 611458

This gene encodes a member of the glycosyl hydrolase 35 family of proteins. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate the mature lysosomal enzyme. This enzyme catalyzes the hydrolysis of a terminal beta-linked galactose residue from ganglioside substrates and other glycoconjugates. Mutations in this gene may result in GM1-gangliosidosis and Morquio B syndrome. [provided by RefSeq, Nov 2015]

GeneReviewsOMIMResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

GM1-gangliosidosis, type IMIM #230500
AR
GM1-gangliosidosis, type IIMIM #230600
AR
GM1-gangliosidosis, type IIIMIM #230650
AR
Mucopolysaccharidosis type IVB (Morquio)MIM #253010
AR

Clinical highlights

Gene-disease validity (ClinGen)
GM1 gangliosidosis · ARDefinitivesufficient evidence for diagnostic panels2 gene-disease associations curated in total
Interpreting a novel variant
Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.
6
Active trials
63
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
0.86
LOEUF
LOF
Mechanism· G2P
📖
GeneReview available — GLB1
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
0.86LOEUF
pLI 0.000
Z-score 2.20
OE 0.59 (0.42–0.86)
Tolerant

Typical tolerance to LoF variation

Missense Constraint?
0.79Z-score
OE missense 0.88 (0.81–0.97)
333 obs / 376.4 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.59 (0.42–0.86)
0≤0.351.4
Missense OE?0.88 (0.81–0.97)
0≤0.61.4
Synonymous OE?0.95
0≤1.21.6
LoF obs/exp: 20 / 33.8Missense obs/exp: 333 / 376.4Syn Z: 0.43

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

GLB1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov
HIV InfectionsAlcohol DrinkingAging

Precision Microbiota Interventions for Senoreduction Trial

NOT YET RECRUITING
NCT07462767Phase PHASE1, PHASE2Louisiana State University Health Sciences Center in New OrleansStarted 2026-04-01
Limosilactobacillus reuteriBlueberry extract
Obesity & Overweight

Supplementation With Sirtuin Activators in Women With Increased Body Weight

RECRUITING
NCT07245979Phase NAPoznan University of Life SciencesStarted 2025-10-08
Sirtuin activatorsPlacebo
Lactose IntoleranceLactose IntolerantLactase Persistence

Milk for Diabetes Prevention

RECRUITING
NCT06513026Phase NAAlbert Einstein College of MedicineStarted 2026-05-15
Lactose-Containing MilkLactose-Free Milk
GM1 GangliosidosisGM1 Gangliosidosis, Type IGM1 Gangliosidosis, Type 2

Study of Safety, Tolerability and Efficacy of PBGM01 in Pediatric Participants With GM1 Gangliosidosis

ACTIVE NOT RECRUITING
NCT04713475Phase PHASE1, PHASE2Gemma BiotherapeuticsStarted 2021-03-17
PBGM01
Lysosomal DiseasesGangliosidosisGM1

A Phase 1/2 Study of Intravenous Gene Transfer With an AAV9 Vector Expressing Human Beta-galactosidase in Type I and Type II GM1 Gangliosidosis

RECRUITING
NCT03952637Phase PHASE1, PHASE2National Human Genome Research Institute (NHGRI)Started 2019-08-19
AAV9-GLB1Abdominal ultrasoundRituximab
GM1 GangliosidosesGM1 Gangliosidosis, Type IGM1 Gangliosidosis, Type 2

Prenatal Intravenous Gene Transfer With an AAV9 Vector Expressing Human Beta-galactosidase in Type I and Type II GM1 Gangliosidosis Clinical Trial

NOT YET RECRUITING
NCT07479953Phase PHASE1Tippi MackenzieStarted 2027-01-01
Gene Transfer with an AAV9 Vector Expressing Human ß-galactosidase

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients