chr3-49132402-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 4P and 4B. PM1PM2BP4_Strong

The NM_002292.4(LAMB2):c.253G>A(p.Glu85Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000217 in 1,614,164 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00021 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00022 ( 0 hom. )

Consequence

LAMB2
NM_002292.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 5.84

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM1

In a domain Laminin N-terminal (size 239) in uniprot entity LAMB2_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_002292.4

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.05063072).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LAMB2	NM_002292.4 link	c.253G>A	p.Glu85Lys	missense_variant	Exon 3 of 32	ENST00000305544.9	NP_002283.3	P55268
LAMB2	XM_005265127.5 link	c.253G>A	p.Glu85Lys	missense_variant	Exon 4 of 33		XP_005265184.1	P55268

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
LAMB2	ENST00000305544.9 link	c.253G>A	p.Glu85Lys	missense_variant	Exon 3 of 32	1	NM_002292.4	ENSP00000307156.4	P55268
LAMB2	ENST00000418109.5 link	c.253G>A	p.Glu85Lys	missense_variant	Exon 4 of 33	1		ENSP00000388325.1	P55268
LAMB2	ENST00000494831.1 link	c.-27-248G>A		intron_variant	Intron 1 of 4	2		ENSP00000444751.1	F5H520

Frequencies

GnomAD3 genomes

AF:

0.000210

AC:

AN:

152198

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00461

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000176

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000322

AC:

AN:

251456

Hom.:

AF XY:

0.000324

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00407

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000229

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000255

Gnomad OTH exome

AF:

0.000326

GnomAD4 exome

AF:

0.000218

AC:

319

AN:

1461848

Hom.:

Cov.:

AF XY:

0.000224

AC XY:

163

AN XY:

727222

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00448

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.000278

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000126

Gnomad4 OTH exome

AF:

0.000480

GnomAD4 genome

AF:

0.000210

AC:

AN:

152316

Hom.:

Cov.:

AF XY:

0.000201

AC XY:

AN XY:

74478

show subpopulations

Gnomad4 AFR

AF:

0.0000481

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00461

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000176

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000474

Hom.:

Bravo

AF:

0.000223

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000698

AC:

ExAC

AF:

0.000247

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000237

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

LAMB2-related infantile-onset nephrotic syndrome

Uncertain:2

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Jan 16, 2020

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

not provided

Uncertain:1

Jan 05, 2023

Mayo Clinic Laboratories, Mayo Clinic

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Pierson syndrome

Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Pierson syndrome;C3280113:LAMB2-related infantile-onset nephrotic syndrome

Benign:1

Sep 14, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.26

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Benign

-0.13

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.22

T;T

Eigen

Uncertain

0.26

Eigen_PC

Uncertain

0.25

FATHMM_MKL

Uncertain

0.83

LIST_S2

Uncertain

0.88

.;D

M_CAP

Benign

0.029

MetaRNN

Benign

0.051

T;T

MetaSVM

Benign

-0.50

MutationAssessor

Benign

1.9

L;L

PrimateAI

Uncertain

0.76

PROVEAN

Benign

-1.6

N;N

REVEL

Uncertain

0.31

Sift

Benign

0.26

T;T

Sift4G

Benign

0.57

T;T

Polyphen

0.97

D;D

Vest4

0.71

MVP

0.67

MPC

1.4

ClinPred

0.078

GERP RS

4.4

Varity_R

0.22

gMVP

0.71

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.090

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over