chr6-129391497-A-G

Position:

• chr6-129391497-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000426.4(LAMA2):​c.5078A>G​(p.Asn1693Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,402 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LAMA2 NM_000426.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 5.11

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.25726664).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LAMA2	NM_000426.4	c.5078A>G	p.Asn1693Ser	missense_variant	36/65	ENST00000421865.3	NP_000417.3
LAMA2	NM_001079823.2	c.5078A>G	p.Asn1693Ser	missense_variant	36/64		NP_001073291.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LAMA2	ENST00000421865.3	c.5078A>G	p.Asn1693Ser	missense_variant	36/65	5	NM_000426.4	ENSP00000400365
LAMA2	ENST00000618192.5	c.5342A>G	p.Asn1781Ser	missense_variant	37/66	5		ENSP00000480802	P1
LAMA2	ENST00000617695.5	c.5078A>G	p.Asn1693Ser	missense_variant	36/64	5		ENSP00000481744
LAMA2	ENST00000687590.1	n.1498A>G		non_coding_transcript_exon_variant	4/5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461402 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726998

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

LAMA2-related muscular dystrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 20, 2022

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt LAMA2 protein function. ClinVar contains an entry for this variant (Variation ID: 543857). This variant has not been reported in the literature in individuals affected with LAMA2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 1693 of the LAMA2 protein (p.Asn1693Ser). -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

May 10, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.079
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.56
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Benign	0.011	.;T;T
Eigen	Benign	0.095
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.85	D;D;D
M_CAP	Benign	0.0082	T
MetaRNN	Benign	0.26	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Uncertain	2.3	.;.;M
MutationTaster	Benign	0.94	D
PrimateAI	Benign	0.44	T
PROVEAN	Benign	-0.26	.;.;N
REVEL	Benign	0.17
Sift	Benign	0.48	.;.;T
Polyphen		0.48	.;.;P
Vest4		0.31
MutPred		0.54		Loss of catalytic residue at N1693 (P = 0.0196);Loss of catalytic residue at N1693 (P = 0.0196);Loss of catalytic residue at N1693 (P = 0.0196);
MVP		0.56
MPC		0.077
ClinPred		0.75	D
GERP RS		6.1
Varity_R		0.13
gMVP		0.19

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

Other links and lift over

dbSNP: rs1554286924; hg19: chr6-129712642;