3-49131128-C-T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_ModeratePP5_Moderate

The NM_002292.4(LAMB2):​c.737G>A​(p.Arg246Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000659 in 151,842 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R246W) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Consequence

LAMB2
NM_002292.4 missense

Scores

13
5
1

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 7.56

Publications

29 publications found
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 Gene-Disease associations (from GenCC):
  • Pierson syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, PanelApp Australia, Orphanet
  • LAMB2-related infantile-onset nephrotic syndrome
    Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 10 ACMG points.

PM1
In a domain Laminin N-terminal (size 239) in uniprot entity LAMB2_HUMAN there are 7 pathogenic changes around while only 2 benign (78%) in NM_002292.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-49131129-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 14530.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 3-49131128-C-T is Pathogenic according to our data. Variant chr3-49131128-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 14534.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMB2NM_002292.4 linkc.737G>A p.Arg246Gln missense_variant Exon 7 of 32 ENST00000305544.9 NP_002283.3 P55268
LAMB2XM_005265127.5 linkc.737G>A p.Arg246Gln missense_variant Exon 8 of 33 XP_005265184.1 P55268

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMB2ENST00000305544.9 linkc.737G>A p.Arg246Gln missense_variant Exon 7 of 32 1 NM_002292.4 ENSP00000307156.4 P55268
LAMB2ENST00000418109.5 linkc.737G>A p.Arg246Gln missense_variant Exon 8 of 33 1 ENSP00000388325.1 P55268
LAMB2ENST00000494831.1 linkc.290G>A p.Arg97Gln missense_variant Exon 5 of 5 2 ENSP00000444751.1 F5H520

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151842
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
Cov.:
33
GnomAD4 genome
AF:
0.00000659
AC:
1
AN:
151842
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74154
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41294
American (AMR)
AF:
0.00
AC:
0
AN:
15252
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5152
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67936
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Pierson syndrome;C3280113:LAMB2-related infantile-onset nephrotic syndrome Pathogenic:1
Mar 19, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

LAMB2-related infantile-onset nephrotic syndrome Pathogenic:1
Sep 01, 2006
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.64
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.42
CADD
Pathogenic
36
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.64
D;D;D
Eigen
Pathogenic
0.97
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Pathogenic
0.98
.;D;D
M_CAP
Uncertain
0.13
D
MetaRNN
Pathogenic
0.97
D;D;D
MetaSVM
Pathogenic
0.89
D
MutationAssessor
Pathogenic
3.5
M;M;.
PhyloP100
7.6
PrimateAI
Uncertain
0.71
T
PROVEAN
Uncertain
-3.9
D;D;D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.0030
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
1.0
D;D;.
Vest4
0.93
MutPred
0.91
Loss of MoRF binding (P = 0.0404);Loss of MoRF binding (P = 0.0404);.;
MVP
0.92
MPC
1.4
ClinPred
1.0
D
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.87
gMVP
0.87
Mutation Taster
=22/78
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.95
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.95
Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs121912491; hg19: chr3-49168561; API