rs1555016408

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_006876.3(B4GAT1):​c.1009A>T​(p.Thr337Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,612,730 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

B4GAT1
NM_006876.3 missense

Scores

18

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.241

Publications

0 publications found
Variant links:
Genes affected
B4GAT1 (HGNC:15685): (beta-1,4-glucuronyltransferase 1) This gene encodes a member of the beta-1,3-N-acetylglucosaminyltransferase family. This enzyme is a type II transmembrane protein. It is essential for the synthesis of poly-N-acetyllactosamine, a determinant for the blood group i antigen. [provided by RefSeq, Jul 2008]
B4GAT1 Gene-Disease associations (from GenCC):
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A13
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen
  • muscular dystrophy-dystroglycanopathy, type A
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.06772432).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
B4GAT1NM_006876.3 linkc.1009A>T p.Thr337Ser missense_variant Exon 1 of 2 ENST00000311181.5 NP_006867.1 O43505A0A024R5F9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
B4GAT1ENST00000311181.5 linkc.1009A>T p.Thr337Ser missense_variant Exon 1 of 2 1 NM_006876.3 ENSP00000309096.4 O43505

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152066
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460664
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
726452
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.0000224
AC:
1
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26112
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39666
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86228
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53166
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111190
Other (OTH)
AF:
0.00
AC:
0
AN:
60354
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152066
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74276
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41408
American (AMR)
AF:
0.0000655
AC:
1
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68002
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.675
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A13 Uncertain:1
Oct 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with serine, which is neutral and polar, at codon 337 of the B4GAT1 protein (p.Thr337Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with B4GAT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 474247). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt B4GAT1 protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.067
BayesDel_addAF
Benign
-0.36
T
BayesDel_noAF
Benign
-0.76
CADD
Benign
4.3
DANN
Benign
0.84
DEOGEN2
Benign
0.16
T
Eigen
Benign
-0.96
Eigen_PC
Benign
-0.82
FATHMM_MKL
Benign
0.24
N
LIST_S2
Benign
0.47
T
M_CAP
Benign
0.0040
T
MetaRNN
Benign
0.068
T
MetaSVM
Benign
-1.0
T
PhyloP100
-0.24
PrimateAI
Benign
0.42
T
PROVEAN
Benign
-0.19
N
REVEL
Benign
0.081
Sift
Benign
0.80
T
Sift4G
Benign
0.79
T
Polyphen
0.0
B
Vest4
0.061
MutPred
0.28
Gain of disorder (P = 0.0707);
MVP
0.014
MPC
0.75
ClinPred
0.046
T
GERP RS
-3.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.057
gMVP
0.64
Mutation Taster
=91/9
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs1555016408; hg19: chr11-66114008; API