6-129401308-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM2 PM5 BP4_Moderate

The NM_000426.4(LAMA2):c.5530C>G(p.Arg1844Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,684 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1844C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: LAMA2 NM_000426.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.873

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr6-129401308-C-A is described in Lovd as [Pathogenic].
• BP4: Computational evidence support a benign effect (MetaRNN=0.13772959).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMA2	NM_000426.4	c.5530C>G	p.Arg1844Gly	missense_variant	38/65	ENST00000421865.3
LAMA2	NM_001079823.2	c.5530C>G	p.Arg1844Gly	missense_variant	38/64

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMA2	ENST00000421865.3	c.5530C>G	p.Arg1844Gly	missense_variant	38/65	5	NM_000426.4
LAMA2	ENST00000618192.5	c.5794C>G	p.Arg1932Gly	missense_variant	39/66	5		P1
LAMA2	ENST00000617695.5	c.5530C>G	p.Arg1844Gly	missense_variant	38/64	5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250736 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135504

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458684 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 725880

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.073
BayesDel_addAF	Benign	-0.28	T
BayesDel_noAF	Benign	-0.47
Cadd	Benign	20
Dann	Uncertain	0.99
Eigen	Benign	-0.46
Eigen_PC	Benign	-0.34
FATHMM_MKL	Benign	0.21	N
LIST_S2	Benign	0.81	T;T;T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.14	T;T;T
MetaSVM	Benign	-0.99	T
MutationTaster	Benign	0.97	N
PrimateAI	Benign	0.23	T
Polyphen		0.085	.;.;B
Vest4		0.39
MutPred		0.56		Loss of stability (P = 0.0254);Loss of stability (P = 0.0254);Loss of stability (P = 0.0254);
MVP		0.50
MPC		0.12
ClinPred		0.18	T
GERP RS		4.4
Varity_R		0.13
gMVP		0.18

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: rs56173620; hg19: chr6-129722453;