rs886038293

Variant names:

• chr6-129454287-A-C
• rs886038293
• NM_000426.4:c.6706A>C

Your query was ambiguous. Multiple possible variants found:

• chr6-129454287-A-C
• chr6-129454287-A-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_000426.4(LAMA2):​c.6706A>C​(p.Arg2236Arg) variant causes a splice region, synonymous change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: LAMA2 NM_000426.4 splice_region, synonymous
• Scores: Splicing: ADA: 0.6285
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 5.30

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]

ENSG00000226149 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 6-129454287-A-C is Benign according to our data. Variant chr6-129454287-A-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 256082.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}. Variant chr6-129454287-A-C is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LAMA2	NM_000426.4	c.6706A>C	p.Arg2236Arg	splice_region_variant, synonymous_variant	Exon 47 of 65	ENST00000421865.3	NP_000417.3
LAMA2	NM_001079823.2	c.6706A>C	p.Arg2236Arg	splice_region_variant, synonymous_variant	Exon 47 of 64		NP_001073291.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LAMA2	ENST00000421865.3	c.6706A>C	p.Arg2236Arg	splice_region_variant, synonymous_variant	Exon 47 of 65	5	NM_000426.4	ENSP00000400365.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

LAMA2-related muscular dystrophy Uncertain:1

May 20, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects codon 2236 of the LAMA2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the LAMA2 protein. It affects a nucleotide within the consensus splice site. This variant is not present in population databases (gnomAD no frequency). 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: 256082). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

not provided Uncertain:1

Aug 14, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis suggests this variant may impact gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; Has not been previously published as pathogenic or benign to our knowledge -

not specified Benign:1

-

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	21
DANN	Benign	0.73

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.63
dbscSNV1_RF	Benign	0.52
SpliceAI score (max)		0.41		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.41		Position offset: -20

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs886038293; hg19: chr6-129775432;