rs398123388

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PP3_StrongPP5

The NM_000426.4(LAMA2):c.830C>T(p.Ser277Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000106 in 1,607,586 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. S277S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:4

Conservation

PhyloP100: 7.79

Variant links:

Genes affected

LAMA2 (HGNC:6482): (laminin subunit alpha 2) Laminin, an extracellular protein, is a major component of the basement membrane. It is thought to mediate the attachment, migration, and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components. It is composed of three subunits, alpha, beta, and gamma, which are bound to each other by disulfide bonds into a cross-shaped molecule. This gene encodes the alpha 2 chain, which constitutes one of the subunits of laminin 2 (merosin) and laminin 4 (s-merosin). Mutations in this gene have been identified as the cause of congenital merosin-deficient muscular dystrophy. Two transcript variants encoding different proteins have been found for this gene. [provided by RefSeq, Jul 2008]

LAMA2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.973

PP5

Variant 6-129146969-C-T is Pathogenic according to our data. Variant chr6-129146969-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 92990.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=4, Likely_pathogenic=2}. Variant chr6-129146969-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMA2	NM_000426.4 linkuse as main transcript	c.830C>T	p.Ser277Leu	missense_variant	6/65	ENST00000421865.3
LAMA2	NM_001079823.2 linkuse as main transcript	c.830C>T	p.Ser277Leu	missense_variant	6/64

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMA2	ENST00000421865.3 linkuse as main transcript	c.830C>T	p.Ser277Leu	missense_variant	6/65	5	NM_000426.4

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152038

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.000480

GnomAD3 exomes

AF:

0.00000798

AC:

AN:

250744

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135498

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

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:

0.00000884

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000824

AC:

AN:

1455548

Hom.:

Cov.:

AF XY:

0.00000828

AC XY:

AN XY:

724442

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000994

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152038

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74280

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000288

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.000480

Bravo

AF:

0.0000113

EpiCase

AF:

0.0000546

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2Uncertain:4

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Merosin deficient congenital muscular dystrophy

Pathogenic:1Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 27, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Oct 16, 2017	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	May 22, 2013	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Nov 06, 2019	- -

Muscular dystrophy, limb-girdle, autosomal recessive 23

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Hadassah Hebrew University Medical Center

- -

LAMA2-related muscular dystrophy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 08, 2022

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 277 of the LAMA2 protein (p.Ser277Leu). This variant is present in population databases (rs398123388, gnomAD 0.01%). This missense change has been observed in individual(s) with LAMA2-related muscular dystrophy (PMID: 24225367). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 92990). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.97

BayesDel_addAF

Pathogenic

0.35

BayesDel_noAF

Pathogenic

0.35

Cadd

Pathogenic

Dann

Pathogenic

1.0

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.95

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.97

D;D;D

M_CAP

Pathogenic

0.44

MetaRNN

Pathogenic

0.97

D;D;D

MetaSVM

Uncertain

0.54

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.76

Polyphen

1.0

.;.;D

Vest4

0.97

MutPred

0.81

Gain of ubiquitination at K279 (P = 0.0683);Gain of ubiquitination at K279 (P = 0.0683);Gain of ubiquitination at K279 (P = 0.0683);

MVP

0.95

MPC

0.45

ClinPred

1.0

GERP RS

5.8

Varity_R

0.93

gMVP

0.92

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.080

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