6-129260736-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000426.4(LAMA2):​c.2122G>A​(p.Ala708Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,611,454 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 missense

Scores

2
6
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.34
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.942

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
LAMA2NM_000426.4 linkuse as main transcriptc.2122G>A p.Ala708Thr missense_variant 15/65 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkuse as main transcriptc.2122G>A p.Ala708Thr missense_variant 15/64 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkuse as main transcriptc.2122G>A p.Ala708Thr missense_variant 15/655 NM_000426.4 ENSP00000400365
LAMA2ENST00000618192.5 linkuse as main transcriptc.2122G>A p.Ala708Thr missense_variant 15/665 ENSP00000480802 P1
LAMA2ENST00000617695.5 linkuse as main transcriptc.2122G>A p.Ala708Thr missense_variant 15/645 ENSP00000481744

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152000
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251260
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135798
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:
0.00000274
AC:
4
AN:
1459454
Hom.:
0
Cov.:
30
AF XY:
0.00000413
AC XY:
3
AN XY:
726184
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000360
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152000
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74224
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoMay 18, 2016- -
LAMA2-related muscular dystrophy Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 31, 2021This sequence change replaces alanine with threonine at codon 708 of the LAMA2 protein (p.Ala708Thr). The alanine residue is moderately conserved and there is a small physicochemical difference between alanine and threonine. This variant is present in population databases (rs777765933, ExAC 0.001%). This variant has not been reported in the literature in individuals affected with LAMA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 435711). 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: "Possibly 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
Benign
0.23
BayesDel_addAF
Benign
-0.039
T
BayesDel_noAF
Benign
-0.29
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.036
.;T;T
Eigen
Benign
0.048
Eigen_PC
Benign
0.051
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.84
T;T;T
M_CAP
Benign
0.040
D
MetaRNN
Pathogenic
0.94
D;D;D
MetaSVM
Benign
-0.86
T
MutationAssessor
Uncertain
2.1
.;.;M
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-2.7
.;.;D
REVEL
Uncertain
0.31
Sift
Uncertain
0.0040
.;.;D
Polyphen
0.45
.;.;B
Vest4
0.65
MutPred
0.85
Gain of glycosylation at A708 (P = 0.0221);Gain of glycosylation at A708 (P = 0.0221);Gain of glycosylation at A708 (P = 0.0221);
MVP
0.72
MPC
0.36
ClinPred
0.95
D
GERP RS
4.7
Varity_R
0.36
gMVP
0.80

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs777765933; hg19: chr6-129581881; COSMIC: COSV70342696; API