3-49123554-T-A

Variant summary

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

The NM_002292.4(LAMB2):​c.3875A>T​(p.Asn1292Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000263 in 1,614,200 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N1292S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0014 ( 3 hom., cov: 33)
Exomes 𝑓: 0.00014 ( 0 hom. )

Consequence

LAMB2
NM_002292.4 missense

Scores

1
5
13

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 4.09
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]

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=0.015163004).
BP6
Variant 3-49123554-T-A is Benign according to our data. Variant chr3-49123554-T-A is described in ClinVar as [Likely_benign]. Clinvar id is 472483.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00144 (219/152344) while in subpopulation AFR AF= 0.00462 (192/41572). AF 95% confidence interval is 0.00408. There are 3 homozygotes in gnomad4. There are 109 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
BS2
High Homozygotes in GnomAd4 at 3 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
LAMB2NM_002292.4 linkuse as main transcriptc.3875A>T p.Asn1292Ile missense_variant 25/32 ENST00000305544.9
LAMB2XM_005265127.5 linkuse as main transcriptc.3875A>T p.Asn1292Ile missense_variant 26/33

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
LAMB2ENST00000305544.9 linkuse as main transcriptc.3875A>T p.Asn1292Ile missense_variant 25/321 NM_002292.4 P1
LAMB2ENST00000418109.5 linkuse as main transcriptc.3875A>T p.Asn1292Ile missense_variant 26/331 P1
LAMB2ENST00000469665.1 linkuse as main transcriptn.105A>T non_coding_transcript_exon_variant 2/32
LAMB2ENST00000477225.1 linkuse as main transcriptn.306A>T non_coding_transcript_exon_variant 2/22

Frequencies

GnomAD3 genomes
AF:
0.00143
AC:
217
AN:
152226
Hom.:
3
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00458
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00124
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.000955
GnomAD3 exomes
AF:
0.000294
AC:
74
AN:
251486
Hom.:
1
AF XY:
0.000221
AC XY:
30
AN XY:
135916
show subpopulations
Gnomad AFR exome
AF:
0.00344
Gnomad AMR exome
AF:
0.000318
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:
0.00000879
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000141
AC:
206
AN:
1461856
Hom.:
0
Cov.:
34
AF XY:
0.000124
AC XY:
90
AN XY:
727236
show subpopulations
Gnomad4 AFR exome
AF:
0.00415
Gnomad4 AMR exome
AF:
0.000358
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000812
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000450
Gnomad4 OTH exome
AF:
0.000646
GnomAD4 genome
AF:
0.00144
AC:
219
AN:
152344
Hom.:
3
Cov.:
33
AF XY:
0.00146
AC XY:
109
AN XY:
74500
show subpopulations
Gnomad4 AFR
AF:
0.00462
Gnomad4 AMR
AF:
0.00124
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000882
Gnomad4 OTH
AF:
0.000945
Alfa
AF:
0.0000545
Hom.:
0
Bravo
AF:
0.00176
ESP6500AA
AF:
0.00386
AC:
17
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000412
AC:
50

ClinVar

Significance: Likely benign
Submissions summary: Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Pierson syndrome;C3280113:LAMB2-related infantile-onset nephrotic syndrome Benign:1
Likely benign, criteria provided, single submitterclinical testingInvitaeJan 19, 2024- -
LAMB2-related disorder Benign:1
Likely benign, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesMay 21, 2021This 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). -
LAMB2-related infantile-onset nephrotic syndrome Benign:1
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 12, 2018This 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -
Pierson syndrome Benign:1
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 12, 2018This 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.28
BayesDel_addAF
Benign
-0.40
T
BayesDel_noAF
Benign
-0.34
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Benign
0.36
T;T
Eigen
Uncertain
0.57
Eigen_PC
Uncertain
0.59
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.86
.;D
M_CAP
Benign
0.019
T
MetaRNN
Benign
0.015
T;T
MetaSVM
Benign
-0.95
T
MutationAssessor
Benign
2.0
M;M
MutationTaster
Benign
1.0
D;D
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-3.9
D;D
REVEL
Benign
0.22
Sift
Benign
0.14
T;T
Sift4G
Benign
0.18
T;T
Polyphen
1.0
D;D
Vest4
0.66
MVP
0.54
MPC
0.39
ClinPred
0.041
T
GERP RS
5.8
Varity_R
0.41
gMVP
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.

Other links and lift over

dbSNP: rs148246465; hg19: chr3-49160987; API