9-33113555-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_001497.4(B4GALT1):​c.1096A>T​(p.Met366Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000057 in 1,614,084 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000059 ( 0 hom. )

Consequence

B4GALT1
NM_001497.4 missense

Scores

6
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 5.97
Variant links:
Genes affected
B4GALT1 (HGNC:924): (beta-1,4-galactosyltransferase 1) This gene is one of seven beta-1,4-galactosyltransferase (beta4GalT) genes. They encode type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose; all transfer galactose in a beta1,4 linkage to similar acceptor sugars: GlcNAc, Glc, and Xyl. Each beta4GalT has a distinct function in the biosynthesis of different glycoconjugates and saccharide structures. As type II membrane proteins, they have an N-terminal hydrophobic signal sequence that directs the protein to the Golgi apparatus and which then remains uncleaved to function as a transmembrane anchor. By sequence similarity, the beta4GalTs form four groups: beta4GalT1 and beta4GalT2, beta4GalT3 and beta4GalT4, beta4GalT5 and beta4GalT6, and beta4GalT7. This gene is unique among the beta4GalT genes because it encodes an enzyme that participates both in glycoconjugate and lactose biosynthesis. For the first activity, the enzyme adds galactose to N-acetylglucosamine residues that are either monosaccharides or the nonreducing ends of glycoprotein carbohydrate chains. The second activity is restricted to lactating mammary tissues where the enzyme forms a heterodimer with alpha-lactalbumin to catalyze UDP-galactose + D-glucose <=> UDP + lactose. The two enzymatic forms result from alternate transcription initiation sites and post-translational processing. Two transcripts, which differ only at the 5' end, with approximate lengths of 4.1 kb and 3.9 kb encode the same protein. The longer transcript encodes the type II membrane-bound, trans-Golgi resident protein involved in glycoconjugate biosynthesis. The shorter transcript encodes a protein which is cleaved to form the soluble lactose synthase. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.340712).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
B4GALT1NM_001497.4 linkuse as main transcriptc.1096A>T p.Met366Leu missense_variant 6/6 ENST00000379731.5 NP_001488.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
B4GALT1ENST00000379731.5 linkuse as main transcriptc.1096A>T p.Met366Leu missense_variant 6/61 NM_001497.4 ENSP00000369055 P1P15291-1
B4GALT1ENST00000535206.5 linkuse as main transcriptc.649-8774A>T intron_variant 1 ENSP00000440341

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152190
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000636
AC:
16
AN:
251466
Hom.:
0
AF XY:
0.0000515
AC XY:
7
AN XY:
135906
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000132
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000588
AC:
86
AN:
1461894
Hom.:
0
Cov.:
32
AF XY:
0.0000523
AC XY:
38
AN XY:
727248
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000746
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74346
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000882
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000564
Hom.:
0
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000741
AC:
9
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 21, 2023This sequence change replaces methionine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 366 of the B4GALT1 protein (p.Met366Leu). This variant is present in population databases (rs377678566, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with B4GALT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 449848). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt B4GALT1 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. -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxAug 17, 2017The M366L variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The M366L variant is observed in 9/66730 (0.01%) alleles from individuals of European background, in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The M366L variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. This substitution occurs at a position that is conserved across species. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. In summary, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.34
BayesDel_addAF
Benign
-0.11
T
BayesDel_noAF
Benign
-0.17
CADD
Benign
22
DANN
Benign
0.97
DEOGEN2
Benign
0.37
T
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Benign
0.84
T
M_CAP
Benign
0.0097
T
MetaRNN
Benign
0.34
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Uncertain
2.4
M
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
-2.0
N
REVEL
Benign
0.18
Sift
Benign
0.31
T
Sift4G
Benign
1.0
T
Polyphen
0.75
P
Vest4
0.51
MutPred
0.65
Loss of disorder (P = 0.1588);
MVP
0.65
MPC
0.78
ClinPred
0.14
T
GERP RS
6.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.76
gMVP
0.83

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs377678566; hg19: chr9-33113553; API