3-49126004-G-A

Position:

chr3-49126004-G-A

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_ModerateBP6BP7BS1BS2

The NM_002292.4(LAMB2):c.2307C>T(p.Leu769=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0035 in 1,614,188 control chromosomes in the GnomAD database, including 24 homozygotes. 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 0.0025 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0036 ( 24 hom. )

Consequence

LAMB2
NM_002292.4 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:7

Conservation

PhyloP100: 3.51

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 -12 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.45).

BP6

Variant 3-49126004-G-A is Benign according to our data. Variant chr3-49126004-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 258603.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Uncertain_significance=1, Benign=1}. Variant chr3-49126004-G-A is described in Lovd as [Benign].

BP7

Synonymous conserved (PhyloP=3.51 with no splicing effect.

BS1

Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.00249 (379/152302) while in subpopulation SAS AF= 0.00498 (24/4824). AF 95% confidence interval is 0.00343. There are 0 homozygotes in gnomad4. There are 183 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

BS2

High Homozygotes in GnomAdExome4 at 24 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMB2	NM_002292.4 linkuse as main transcript	c.2307C>T	p.Leu769=	synonymous_variant	17/32	ENST00000305544.9
LAMB2	XM_005265127.5 linkuse as main transcript	c.2307C>T	p.Leu769=	synonymous_variant	18/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMB2	ENST00000305544.9 linkuse as main transcript	c.2307C>T	p.Leu769=	synonymous_variant	17/32	1	NM_002292.4	P1

Frequencies

GnomAD3 genomes

AF:

0.00249

AC:

379

AN:

152184

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000917

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00321

Gnomad ASJ

AF:

0.00173

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00497

Gnomad FIN

AF:

0.000188

Gnomad MID

AF:

0.00633

Gnomad NFE

AF:

0.00370

Gnomad OTH

AF:

0.00287

GnomAD3 exomes

AF:

0.00293

AC:

737

AN:

251304

Hom.:

AF XY:

0.00338

AC XY:

459

AN XY:

135856

show subpopulations

Gnomad AFR exome

AF:

0.000616

Gnomad AMR exome

AF:

0.00168

Gnomad ASJ exome

AF:

0.00238

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00784

Gnomad FIN exome

AF:

0.000139

Gnomad NFE exome

AF:

0.00334

Gnomad OTH exome

AF:

0.00343

GnomAD4 exome

AF:

0.00361

AC:

5272

AN:

1461886

Hom.:

Cov.:

AF XY:

0.00372

AC XY:

2702

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.000538

Gnomad4 AMR exome

AF:

0.00179

Gnomad4 ASJ exome

AF:

0.00241

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00712

Gnomad4 FIN exome

AF:

0.000206

Gnomad4 NFE exome

AF:

0.00384

Gnomad4 OTH exome

AF:

0.00285

GnomAD4 genome

AF:

0.00249

AC:

379

AN:

152302

Hom.:

Cov.:

AF XY:

0.00246

AC XY:

183

AN XY:

74478

show subpopulations

Gnomad4 AFR

AF:

0.000914

Gnomad4 AMR

AF:

0.00320

Gnomad4 ASJ

AF:

0.00173

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00498

Gnomad4 FIN

AF:

0.000188

Gnomad4 NFE

AF:

0.00370

Gnomad4 OTH

AF:

0.00284

Alfa

AF:

0.00340

Hom.:

Bravo

AF:

0.00251

Asia WGS

AF:

0.00173

AC:

AN:

3478

EpiCase

AF:

0.00409

EpiControl

AF:

0.00433

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:7

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Benign:3

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2024	LAMB2: BP4, BS2 -
Likely benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

LAMB2-related infantile-onset nephrotic syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

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;C3280113:LAMB2-related infantile-onset nephrotic syndrome

Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 26, 2024

- -

LAMB2-related disorder

Benign:1

Benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Oct 01, 2019

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

Focal segmental glomerulosclerosis

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Mar 01, 2018

- -

Pierson syndrome

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

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 allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.45

CADD

Benign

2.6

DANN

Benign

0.37

Splicing

Name

Calibrated prediction

Score

Prediction

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