B3GNT8

protein-coding

UDP-GlcNAc:betaGal beta-1,3-N-acetylglucosaminyltransferase 8, the group of Beta 3-glycosyltransferases

Gene summary

Enables N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase activity. Involved in poly-N-acetyllactosamine biosynthetic process. Located in extracellular exosome. [provided by Alliance of Genome Resources, Jun 2026]

Previous symbols:

B3GALT7

MANE transcript

NM_001385648.2

Inheritance

—

ClinVar variants

U:78B:9

Top phenotype

—

gnomAD constraint

pLI —, LoF o/e 0.97

Max pathogenic AF

—

Genomic locus

chr19:41,425,359-41,428,730

External References & Databases

Ensembl (ENSG00000177191)

Transcript & Mutation Effects

hg38 • Region Span ~3.4 kb

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GenCC Phenotypes & Disease Associations

Curated gene-disease validity assertions and inheritance patterns

No GenCC data available for this gene.

ClinVar Associated Diseases & Phenotypes

Reported disease conditions connected to B3GNT8 variants in ClinVar

2 Conditions Cataloged

not specifiedTotal: 85

not providedTotal: 4

ClinVar Variants & Pathogenicity by Type

Statistics based on transcript NM_001385648.2. Only rare variants are included.

We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.

Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.

Effect	PathogenicP	Likely pathogenicLP	VUS	Likely benignLB	BenignB	Sum
synonymous					2 clinvar	2
missense			78 clinvar	7 clinvar		85
nonsense						0
start loss						0
frameshift						0
splice donor/acceptor (+/-2bp)						0
Total	0	0	78	7	2	87

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Transcript Catalog

Annotated transcript isoforms across RefSeq and Ensembl databases

Showing 4 of 6 transcripts

Transcript ID	Source	Protein ID	Coding Exons	MANE Status
NM_001385648.2	RefSeq	NP_001372577.1	1	MANE Select
ENST00000691102.1	Ensembl	ENSP00000510371.1	1	MANE Select
NM_198540.2	RefSeq	NP_940942.1	1	Standard
ENST00000321702.2	Ensembl	ENSP00000312700.1	1	Standard

Gene Ontology (GO) Annotations & Pathways

Biological processes, molecular functions, cellular components and pathways

Pathways ConsensusPathDB

Post-translational protein modification
Metabolism of proteins
O-linked glycosylation of mucins
O-linked glycosylation

Biological Process

protein glycosylation
O-glycan processing
poly-N-acetyllactosamine biosynthetic process

Molecular Function

protein binding
acetylgalactosaminyltransferase activity
UDP-galactose:beta-N-acetylglucosamine beta-1,3-galactosyltransferase activity
N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase activity
protein N-acetylglucosaminyltransferase activity

Cellular Component

Golgi membrane
endoplasmic reticulum
Golgi apparatus
integral component of membrane
extracellular exosome

gnomAD Constraint

Source: gnomAD

Gene type: protein_coding
Transcript type: protein_coding
Transcript: ENST00000321702
Coding exons: 1
Length: 3372
Individuals with no LoFs: 125673
Homozygous LoFs: 0
Heterozygous LoFs: 50
Defined: 125723
p: 0.000199

	Z-Score	Observed	Expected	Observed/Expected	Mutation Rate	Total Possible
Missense	0.221	250	260	0.961	0.0000176	2470
Missense (PolyPhen)		90	98.414	0.91451		1034
Synonymous	-1.07	130	115	1.13	0.00000742	931
Loss of Function	0.0931	13	13.4	0.973	9.31e-7	105

Population LoF Frequency

Population	CAF	p-value	Status
African	0.00031	0.00031	rare
Latino/Admixed American	0.00030	0.00029	rare
Ashkenazi Jewish	0	0.0	absent
East Asian	0.00011	0.00011	rare
Finnish	0.000096	0.000092	rare
European (Non-Finnish)	0.00021	0.00020	rare
South Asian	0.00023	0.00023	rare
Other	0.00017	0.00016	rare

dbNSFP Gene Annotations

Source: dbNSFP

Function: FUNCTION: Beta-1,3-N-acetylglucosaminyltransferase that plays a role in the elongation of specific branch structures of multiantennary N-glycans. Has strong activity towards tetraantennary N-glycans and 2,6 triantennary glycans. {ECO:0000269|PubMed:15620693, ECO:0000269|PubMed:15917431}.;

Intolerance Scores

LoFtool: 0.671
RVIS EVS: 0.73
RVIS percentile EVS: 86.27

Essentials

Essential (CRISPR): N
Essential (CRISPR2): N
Essential (gene trap): N
Indispensability pred.: N
Indispensability score: 0.0972

Gene Damage Prediction

	All	Recessive	Dominant
Mendelian	Medium	Medium	Medium
Primary Immunodeficiency	Medium	Medium	Medium
Cancer	Medium	Medium	Medium