rs1211739649

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000426.4(LAMA2):​c.5259delA​(p.Val1754fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,472 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. K1753K) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 1.95

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • congenital merosin-deficient muscular dystrophy 1A
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, G2P
  • LAMA2-related muscular dystrophy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • muscular dystrophy, limb-girdle, autosomal recessive 23
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-129393063-GA-G is Pathogenic according to our data. Variant chr6-129393063-GA-G is described in ClinVar as Pathogenic. ClinVar VariationId is 551353.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA2NM_000426.4 linkc.5259delA p.Val1754fs frameshift_variant Exon 37 of 65 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkc.5259delA p.Val1754fs frameshift_variant Exon 37 of 64 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkc.5259delA p.Val1754fs frameshift_variant Exon 37 of 65 5 NM_000426.4 ENSP00000400365.2 P24043
LAMA2ENST00000618192.5 linkc.5523delA p.Val1842fs frameshift_variant Exon 38 of 66 5 ENSP00000480802.2 A0A087WX80
LAMA2ENST00000617695.5 linkc.5259delA p.Val1754fs frameshift_variant Exon 37 of 64 5 ENSP00000481744.2 A0A087WYF1
LAMA2ENST00000687590.1 linkn.1679delA non_coding_transcript_exon_variant Exon 5 of 5

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
249440
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461472
Hom.:
0
Cov.:
31
AF XY:
0.00000275
AC XY:
2
AN XY:
727050
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44702
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53190
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5760
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111888
Other (OTH)
AF:
0.00
AC:
0
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Merosin deficient congenital muscular dystrophy Pathogenic:2
Mar 31, 2017
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Mar 11, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

LAMA2-related muscular dystrophy Pathogenic:1
Nov 28, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 551353). This premature translational stop signal has been observed in individual(s) with congenital muscular dystrophy, type 1A (PMID: 30055037). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Val1754*) in the LAMA2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LAMA2 are known to be pathogenic (PMID: 18700894, 32904964). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
2.0
Mutation Taster
=0/200
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1211739649; hg19: chr6-129714208; API