rs201307156

Positions:

chr1-183243203-C-T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_005562.3(LAMC2):c.3385C>T(p.Arg1129Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000958 in 1,461,782 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 (★★). Synonymous variant affecting the same amino acid position (i.e. R1129R) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

LAMC2
NM_005562.3 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 0.787

Variant links:

Genes affected

LAMC2 (HGNC:6493): (laminin subunit gamma 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), have 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 gamma chain isoform laminin, gamma 2. The gamma 2 chain, formerly thought to be a truncated version of beta chain (B2t), is highly homologous to the gamma 1 chain; however, it lacks domain VI, and domains V, IV and III are shorter. It is expressed in several fetal tissues but differently from gamma 1, and is specifically localized to epithelial cells in skin, lung and kidney. The gamma 2 chain together with alpha 3 and beta 3 chains constitute laminin 5 (earlier known as kalinin), which is an integral part of the anchoring filaments that connect epithelial cells to the underlying basement membrane. The epithelium-specific expression of the gamma 2 chain implied its role as an epithelium attachment molecule, and mutations in this gene have been associated with junctional epidermolysis bullosa, a skin disease characterized by blisters due to disruption of the epidermal-dermal junction. Two transcript variants resulting from alternative splicing of the 3' terminal exon, and encoding different isoforms of gamma 2 chain, have been described. The two variants are differentially expressed in embryonic tissues, however, the biological significance of the two forms is not known. Transcript variants utilizing alternative polyA_signal have also been noted in literature. [provided by RefSeq, Aug 2011]

LAMC2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 4 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 1-183243203-C-T is Pathogenic according to our data. Variant chr1-183243203-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 370953.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
LAMC2	NM_005562.3 linkuse as main transcript	c.3385C>T	p.Arg1129Ter	stop_gained	23/23	ENST00000264144.5
LAMC2	XM_047420358.1 linkuse as main transcript	c.3328+2812C>T		intron_variant
LAMC2	XM_047420361.1 linkuse as main transcript	c.3328+2812C>T		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMC2	ENST00000264144.5 linkuse as main transcript	c.3385C>T	p.Arg1129Ter	stop_gained	23/23	1	NM_005562.3	P1	Q13753-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251140

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135744

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461782

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727190

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000108

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

ExAC

AF:

0.0000165

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Junctional epidermolysis bullosa, non-Herlitz type

Pathogenic:1

Pathogenic, no assertion criteria provided

research

Department of Pediatrics, Division of Medical Genetics, Faculty of Medicine Ramathibodi Hospital, Mahidol University

Dec 08, 2020

- -

Junctional epidermolysis bullosa gravis of Herlitz

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Counsyl

May 24, 2016

- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Jan 29, 2024

This sequence change creates a premature translational stop signal (p.Arg1129*) in the LAMC2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 65 amino acid(s) of the LAMC2 protein. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with LAMC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 370953). This variant disrupts a region of the LAMC2 protein in which other variant(s) (p.Thr1132Asnfs*38) have been determined to be pathogenic (PMID: 11564184). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.31

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Uncertain

0.46

Eigen_PC

Uncertain

0.22

FATHMM_MKL

Benign

0.16

MutationTaster

Benign

1.0

Vest4

0.64

ClinPred

0.98

GERP RS

3.0

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