B4GALT5

Chr 20

beta-1,4-galactosyltransferase 5

Also known as: B4Gal-T5, BETA4-GALT-IV, beta4Gal-T5, beta4GalT-V, gt-V

The B4GALT5 protein catalyzes the synthesis of lactosylceramide, which is the starting point for ganglioside biosynthesis essential for neuronal maturation, axonal development, and myelin formation. Mutations cause a rare autosomal recessive disorder characterized by severe developmental delays, intellectual disability, and neurological abnormalities. This gene is highly constrained against loss-of-function variants in the population, reflecting its critical role in nervous system development.

Summary from RefSeq, UniProt
Research Assistant →
0
Active trials
16
Pubs (1 yr)
8
P/LP submissions
0%
P/LP missense
0.15
LOEUF· LoF intol.
Mechanism
Clinical SummaryB4GALT5
Population Constraint (gnomAD)
Highly constrained gene — heterozygous loss-of-function variants are very rare in the population (pLI 1.00). One damaged copy is likely sufficient to cause disease.
📋
ClinVar Variants
8 unique Pathogenic / Likely Pathogenic· 27 VUS of 52 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

LoF intolerant — likely haploinsufficient
LoF Constraint
0.15LOEUF
pLI 0.999
Z-score 4.12
OE 0.00 (0.000.15)
Highly constrained

Highly LoF-intolerant (top ~10% of genes)

Missense Constraint
2.37Z-score
OE missense 0.56 (0.480.65)
126 obs / 226.1 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios
LoF OE0.00 (0.000.15)
00.351.4
Missense OE0.56 (0.480.65)
00.61.4
Synonymous OE0.97
01.21.6
LoF obs/exp: 0 / 19.7Missense obs/exp: 126 / 226.1Syn Z: 0.18

ClinVar Variant Classifications

52 submitted variants in ClinVar

Classification Summary

Pathogenic6
Likely Pathogenic2
VUS27
Likely Benign2
Benign4
6
Pathogenic
2
Likely Pathogenic
27
VUS
2
Likely Benign
4
Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
6
0
6
Likely Pathogenic
0
0
2
0
2
VUS
0
25
2
0
27
Likely Benign
0
2
0
0
2
Benign
0
0
1
3
4
Total02711341

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

B4GALT5 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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