NM_152490.5:c.1019A>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_152490.5(B3GALNT2):​c.1019A>G​(p.Tyr340Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000156 in 1,602,564 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

B3GALNT2
NM_152490.5 missense

Scores

2
10
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.08

Publications

0 publications found
Variant links:
Genes affected
B3GALNT2 (HGNC:28596): (beta-1,3-N-acetylgalactosaminyltransferase 2) This gene encodes a member of the glycosyltransferase 31 family. The encoded protein synthesizes GalNAc:beta-1,3GlcNAc, a novel carbohydrate structure, on N- and O-glycans. Alternatively spliced transcript variants that encode different isoforms have been described. [provided by RefSeq, Mar 2013]
B3GALNT2 Gene-Disease associations (from GenCC):
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type a, 11
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics, Genomics England PanelApp
  • autosomal recessive non-syndromic intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscle-eye-brain disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscular dystrophy-dystroglycanopathy, type A
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • intellectual disability
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.843

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
B3GALNT2NM_152490.5 linkc.1019A>G p.Tyr340Cys missense_variant Exon 8 of 12 ENST00000366600.8 NP_689703.1 Q8NCR0-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
B3GALNT2ENST00000366600.8 linkc.1019A>G p.Tyr340Cys missense_variant Exon 8 of 12 1 NM_152490.5 ENSP00000355559.3 Q8NCR0-1

Frequencies

GnomAD3 genomes
AF:
0.0000528
AC:
8
AN:
151650
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.000170
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000657
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
GnomAD2 exomes
AF:
0.0000373
AC:
9
AN:
241348
AF XY:
0.0000154
show subpopulations
Gnomad AFR exome
AF:
0.000126
Gnomad AMR exome
AF:
0.000124
Gnomad ASJ exome
AF:
0.000104
Gnomad EAS exome
AF:
0.000111
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000117
AC:
17
AN:
1450914
Hom.:
0
Cov.:
33
AF XY:
0.0000125
AC XY:
9
AN XY:
721292
show subpopulations
African (AFR)
AF:
0.0000609
AC:
2
AN:
32828
American (AMR)
AF:
0.000117
AC:
5
AN:
42580
Ashkenazi Jewish (ASJ)
AF:
0.0000389
AC:
1
AN:
25686
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39506
South Asian (SAS)
AF:
0.0000120
AC:
1
AN:
83412
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53266
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5052
European-Non Finnish (NFE)
AF:
0.00000631
AC:
7
AN:
1108640
Other (OTH)
AF:
0.0000167
AC:
1
AN:
59944
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000528
AC:
8
AN:
151650
Hom.:
0
Cov.:
31
AF XY:
0.0000540
AC XY:
4
AN XY:
74058
show subpopulations
African (AFR)
AF:
0.000170
AC:
7
AN:
41294
American (AMR)
AF:
0.0000657
AC:
1
AN:
15230
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67942
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type a, 11 Uncertain:2
Sep 07, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 340 of the B3GALNT2 protein (p.Tyr340Cys). This variant is present in population databases (rs773864097, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with B3GALNT2-related conditions. ClinVar contains an entry for this variant (Variation ID: 579191). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25"). 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. -

Dec 10, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Aug 30, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1019A>G (p.Y340C) alteration is located in exon 8 (coding exon 8) of the B3GALNT2 gene. This alteration results from a A to G substitution at nucleotide position 1019, causing the tyrosine (Y) at amino acid position 340 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.33
BayesDel_addAF
Uncertain
0.090
D
BayesDel_noAF
Uncertain
0.13
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Benign
0.26
T
Eigen
Uncertain
0.53
Eigen_PC
Uncertain
0.55
FATHMM_MKL
Pathogenic
0.98
D
M_CAP
Benign
0.029
D
MetaRNN
Pathogenic
0.84
D
MetaSVM
Benign
-0.88
T
MutationAssessor
Benign
0.94
L
PhyloP100
7.1
PrimateAI
Uncertain
0.66
T
PROVEAN
Uncertain
-3.7
D
REVEL
Uncertain
0.46
Sift
Uncertain
0.0010
D
Sift4G
Uncertain
0.0020
D
Polyphen
1.0
D
Vest4
0.88
MutPred
0.62
Loss of methylation at K335 (P = 0.0899);
MVP
0.75
MPC
0.47
ClinPred
0.30
T
GERP RS
5.5
Varity_R
0.37
gMVP
0.71
Mutation Taster
=19/81
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs773864097; hg19: chr1-235621917; API