chr3-49123238-T-C

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_002292.4(LAMB2):​c.4118A>G​(p.Asp1373Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00101 in 1,613,920 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00071 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0010 ( 1 hom. )

Consequence

LAMB2
NM_002292.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2

Conservation

PhyloP100: -0.0330

Publications

9 publications found
Variant links:
Genes affected
LAMB2 (HGNC:6487): (laminin subunit beta 2) Laminins, a family of extracellular matrix glycoproteins, are the major noncollagenous constituent of basement membranes. They have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Laminins, composed of 3 non identical chains: laminin alpha, beta and gamma (formerly A, B1, and B2, respectively), form a cruciform structure consisting of 3 short arms, each formed by a different chain, and a long arm composed of all 3 chains. Each laminin chain is a multidomain protein encoded by a distinct gene. Several isoforms of each chain have been described. Different alpha, beta and gamma chain isomers combine to give rise to different heterotrimeric laminin isoforms which are designated by Arabic numerals in the order of their discovery, i.e. alpha1beta1gamma1 heterotrimer is laminin 1. The biological functions of the different chains and trimer molecules are largely unknown, but some of the chains have been shown to differ with respect to their tissue distribution, presumably reflecting diverse functions in vivo. This gene encodes the beta chain isoform laminin, beta 2. The beta 2 chain contains the 7 structural domains typical of beta chains of laminin, including the short alpha region. However, unlike beta 1 chain, beta 2 has a more restricted tissue distribution. It is enriched in the basement membrane of muscles at the neuromuscular junctions, kidney glomerulus and vascular smooth muscle. Transgenic mice in which the beta 2 chain gene was inactivated by homologous recombination, showed defects in the maturation of neuromuscular junctions and impairment of glomerular filtration. Alternative splicing involving a non consensus 5' splice site (gc) in the 5' UTR of this gene has been reported. It was suggested that inefficient splicing of this first intron, which does not change the protein sequence, results in a greater abundance of the unspliced form of the transcript than the spliced form. The full-length nature of the spliced transcript is not known. [provided by RefSeq, Aug 2011]
LAMB2 Gene-Disease associations (from GenCC):
  • Pierson syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, PanelApp Australia, Orphanet
  • LAMB2-related infantile-onset nephrotic syndrome
    Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0052193403).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMB2NM_002292.4 linkc.4118A>G p.Asp1373Gly missense_variant Exon 26 of 32 ENST00000305544.9 NP_002283.3 P55268
LAMB2XM_005265127.5 linkc.4118A>G p.Asp1373Gly missense_variant Exon 27 of 33 XP_005265184.1 P55268

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMB2ENST00000305544.9 linkc.4118A>G p.Asp1373Gly missense_variant Exon 26 of 32 1 NM_002292.4 ENSP00000307156.4 P55268
LAMB2ENST00000418109.5 linkc.4118A>G p.Asp1373Gly missense_variant Exon 27 of 33 1 ENSP00000388325.1 P55268
LAMB2ENST00000469665.1 linkn.348A>G non_coding_transcript_exon_variant Exon 3 of 3 2
LAMB2ENST00000477225.1 linkn.*87A>G downstream_gene_variant 2

Frequencies

GnomAD3 genomes
AF:
0.000710
AC:
108
AN:
152218
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000193
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000327
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000377
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00129
Gnomad OTH
AF:
0.00144
GnomAD2 exomes
AF:
0.000899
AC:
226
AN:
251444
AF XY:
0.000898
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.000289
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000508
Gnomad NFE exome
AF:
0.00171
Gnomad OTH exome
AF:
0.00130
GnomAD4 exome
AF:
0.00104
AC:
1525
AN:
1461702
Hom.:
1
Cov.:
34
AF XY:
0.00104
AC XY:
754
AN XY:
727162
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.000268
AC:
12
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.000921
AC:
49
AN:
53230
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00129
AC:
1430
AN:
1112012
Other (OTH)
AF:
0.000497
AC:
30
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
115
230
346
461
576
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
46
92
138
184
230
<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:
0.000710
AC:
108
AN:
152218
Hom.:
0
Cov.:
33
AF XY:
0.000619
AC XY:
46
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.000193
AC:
8
AN:
41458
American (AMR)
AF:
0.000327
AC:
5
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.000377
AC:
4
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00129
AC:
88
AN:
68044
Other (OTH)
AF:
0.00144
AC:
3
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
6
12
19
25
31
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:
0.00163
Hom.:
5
Bravo
AF:
0.000695
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.00151
AC:
13
ExAC
AF:
0.00115
AC:
140
EpiCase
AF:
0.00115
EpiControl
AF:
0.00130

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Pierson syndrome;C3280113:LAMB2-related infantile-onset nephrotic syndrome Uncertain:2
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 1373 of the LAMB2 protein (p.Asp1373Gly). This variant is present in population databases (rs112933248, gnomAD 0.2%), and has an allele count higher than expected for a pathogenic variant. This variant has not been reported in the literature in individuals affected with LAMB2-related conditions. ClinVar contains an entry for this variant (Variation ID: 472484). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The glycine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Sep 10, 2021
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Uncertain:1Benign:1
Jan 06, 2020
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 20556798, 27573339) -

Aug 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

LAMB2: BP4 -

LAMB2-related infantile-onset nephrotic syndrome Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Pierson syndrome Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

LAMB2-related disorder Benign:1
Dec 05, 2023
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.059
BayesDel_addAF
Benign
-0.65
T
BayesDel_noAF
Benign
-0.72
CADD
Benign
5.6
DANN
Benign
0.87
DEOGEN2
Benign
0.092
T;T
Eigen
Benign
-1.2
Eigen_PC
Benign
-1.0
FATHMM_MKL
Benign
0.053
N
LIST_S2
Benign
0.68
.;T
M_CAP
Benign
0.0046
T
MetaRNN
Benign
0.0052
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-1.7
N;N
PhyloP100
-0.033
PrimateAI
Benign
0.24
T
PROVEAN
Benign
-1.2
N;N
REVEL
Benign
0.022
Sift
Benign
0.41
T;T
Sift4G
Benign
0.39
T;T
Polyphen
0.0
B;B
Vest4
0.061
MVP
0.13
MPC
0.21
ClinPred
0.0083
T
GERP RS
-1.7
Varity_R
0.038
gMVP
0.40
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs112933248; hg19: chr3-49160671; COSMIC: COSV59732159; COSMIC: COSV59732159; API