rs79677861

Variant summary

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

The NM_002292.4(LAMB2):c.3325G>A(p.Glu1109Lys) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000291 in 1,613,520 control chromosomes in the GnomAD database, including 5 homozygotes. In-silico tool predicts a benign outcome for this variant. 2/2 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.00049 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00027 ( 5 hom. )

Consequence

LAMB2
NM_002292.4 missense, splice_region

Scores

Splicing: ADA: 0.01322

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: 1.41

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=0.008762777).

BP6

Variant 3-49124397-C-T is Benign according to our data. Variant chr3-49124397-C-T is described in ClinVar as [Benign]. Clinvar id is 345988.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.000492 (75/152366) while in subpopulation EAS AF= 0.0137 (71/5180). AF 95% confidence interval is 0.0111. There are 0 homozygotes in gnomad4. There are 40 alleles in male gnomad4 subpopulation. This position pass quality control queck.

BS2

High Homozygotes in GnomAdExome at 3 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMB2	NM_002292.4 linkuse as main transcript	c.3325G>A	p.Glu1109Lys	missense_variant, splice_region_variant	22/32	ENST00000305544.9
LAMB2	XM_005265127.5 linkuse as main transcript	c.3325G>A	p.Glu1109Lys	missense_variant, splice_region_variant	23/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMB2	ENST00000305544.9 linkuse as main transcript	c.3325G>A	p.Glu1109Lys	missense_variant, splice_region_variant	22/32	1	NM_002292.4	P1

Frequencies

GnomAD3 genomes

AF:

0.000486

AC:

AN:

152248

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.0135

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00101

AC:

252

AN:

250468

Hom.:

AF XY:

0.000899

AC XY:

122

AN XY:

135642

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0132

Gnomad SAS exome

AF:

0.000131

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000354

Gnomad OTH exome

AF:

0.000328

GnomAD4 exome

AF:

0.000270

AC:

394

AN:

1461154

Hom.:

Cov.:

AF XY:

0.000244

AC XY:

177

AN XY:

726838

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00844

Gnomad4 SAS exome

AF:

0.000162

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000144

Gnomad4 OTH exome

AF:

0.000480

GnomAD4 genome

AF:

0.000492

AC:

AN:

152366

Hom.:

Cov.:

AF XY:

0.000537

AC XY:

AN XY:

74508

show subpopulations

Gnomad4 AFR

AF:

0.0000240

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.0137

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000365

Hom.:

Bravo

AF:

0.000457

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.00105

AC:

128

Asia WGS

AF:

0.00289

AC:

AN:

3478

ClinVar

Significance: Benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

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

Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 29, 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. -

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

0.29

BayesDel_addAF

Benign

-0.40

BayesDel_noAF

Benign

-0.34

Cadd

Uncertain

Dann

Uncertain

1.0

DEOGEN2

Benign

0.13

T;T

Eigen

Benign

0.18

Eigen_PC

Benign

0.21

FATHMM_MKL

Uncertain

0.96

MetaRNN

Benign

0.0088

T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.4

L;L

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.62

PROVEAN

Uncertain

-2.4

N;N

REVEL

Benign

0.14

Sift

Benign

0.060

T;T

Sift4G

Benign

0.30

T;T

Polyphen

0.99

D;D

Vest4

0.45

MVP

0.34

MPC

0.39

ClinPred

0.056

GERP RS

4.5

Varity_R

0.20

gMVP

0.46

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.013

dbscSNV1_RF

Benign

0.39

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.

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