rs61729458

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_002292.4(LAMB2):c.4774C>T(p.Arg1592Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0022 in 1,613,520 control chromosomes in the GnomAD database, including 72 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.012 ( 38 hom., cov: 33)

Exomes 𝑓: 0.0012 ( 34 hom. )

Consequence

LAMB2
NM_002292.4 missense

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8

Conservation

PhyloP100: 1.92

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 Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.008677244).

BP6

Variant 3-49122170-G-A is Benign according to our data. Variant chr3-49122170-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 258612.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-49122170-G-A is described in Lovd as [Benign].

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0117 (1788/152272) while in subpopulation AFR AF= 0.0412 (1712/41528). AF 95% confidence interval is 0.0396. There are 38 homozygotes in gnomad4. There are 861 alleles in male gnomad4 subpopulation. This position pass quality control queck.

BS2

High Homozygotes in GnomAd at 38 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMB2	NM_002292.4 linkuse as main transcript	c.4774C>T	p.Arg1592Trp	missense_variant	28/32	ENST00000305544.9
LAMB2	XM_005265127.5 linkuse as main transcript	c.4774C>T	p.Arg1592Trp	missense_variant	29/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
LAMB2	ENST00000305544.9 linkuse as main transcript	c.4774C>T	p.Arg1592Trp	missense_variant	28/32	1	NM_002292.4	P1
LAMB2	ENST00000418109.5 linkuse as main transcript	c.4774C>T	p.Arg1592Trp	missense_variant	29/33	1		P1
LAMB2	ENST00000498377.1 linkuse as main transcript	n.429C>T		non_coding_transcript_exon_variant	1/5	2

Frequencies

GnomAD3 genomes

AF:

0.0117

AC:

1786

AN:

152154

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0413

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00347

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000414

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00633

Gnomad NFE

AF:

0.0000735

Gnomad OTH

AF:

0.00669

GnomAD3 exomes

AF:

0.00301

AC:

755

AN:

250922

Hom.:

AF XY:

0.00218

AC XY:

296

AN XY:

135688

show subpopulations

Gnomad AFR exome

AF:

0.0429

Gnomad AMR exome

AF:

0.00130

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000131

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000265

Gnomad OTH exome

AF:

0.00131

GnomAD4 exome

AF:

0.00121

AC:

1763

AN:

1461248

Hom.:

Cov.:

AF XY:

0.00108

AC XY:

782

AN XY:

726924

show subpopulations

Gnomad4 AFR exome

AF:

0.0448

Gnomad4 AMR exome

AF:

0.00163

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000197

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000180

Gnomad4 OTH exome

AF:

0.00237

GnomAD4 genome

AF:

0.0117

AC:

1788

AN:

152272

Hom.:

Cov.:

AF XY:

0.0116

AC XY:

861

AN XY:

74458

show subpopulations

Gnomad4 AFR

AF:

0.0412

Gnomad4 AMR

AF:

0.00346

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000414

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.00662

Alfa

AF:

0.00208

Hom.:

Bravo

AF:

0.0135

ESP6500AA

AF:

0.0420

AC:

185

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.00381

AC:

463

Asia WGS

AF:

0.00202

AC:

AN:

3478

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:3

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 25, 2020	- -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Apr 18, 2018	- -
Benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2023	LAMB2: PP3, BS1, BS2 -

not specified

Benign:1

Benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

- -

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

Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 19, 2024

- -

LAMB2-related infantile-onset nephrotic syndrome

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

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 and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Focal segmental glomerulosclerosis

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Sep 08, 2021

- -

Pierson syndrome

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.49

BayesDel_noAF

Benign

-0.44

Cadd

Pathogenic

Dann

Pathogenic

1.0

DEOGEN2

Benign

0.37

T;T

Eigen

Uncertain

0.49

Eigen_PC

Uncertain

0.46

FATHMM_MKL

Uncertain

0.97

MetaRNN

Benign

0.0087

T;T

MetaSVM

Benign

-1.1

MutationAssessor

Uncertain

2.3

M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Benign

0.42

PROVEAN

Uncertain

-3.9

D;D

REVEL

Benign

0.15

Sift

Uncertain

0.0030

D;D

Sift4G

Benign

0.071

T;T

Polyphen

1.0

D;D

Vest4

0.72

MVP

0.53

MPC

0.69

ClinPred

0.023

GERP RS

4.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.24

gMVP

0.45

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.97

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.97

Position offset: 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