rs143680577

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2PM5PP3_ModeratePP5

The NM_000426.4(LAMA2):​c.437C>A​(p.Ser146Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,612 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S146C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 missense

Scores

10
5
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:1

Conservation

PhyloP100: 2.06

Publications

10 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: Likely_pathogenic. The variant received 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr6-129098213-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 162573.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.868
PP5
Variant 6-129098213-C-A is Pathogenic according to our data. Variant chr6-129098213-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1431679.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA2NM_000426.4 linkc.437C>A p.Ser146Tyr missense_variant Exon 4 of 65 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkc.437C>A p.Ser146Tyr missense_variant Exon 4 of 64 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkc.437C>A p.Ser146Tyr missense_variant Exon 4 of 65 5 NM_000426.4 ENSP00000400365.2 P24043

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152086
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:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251462
AF XY:
0.00000736
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 FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000821
AC:
12
AN:
1461526
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
727100
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86246
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000900
AC:
10
AN:
1111680
Other (OTH)
AF:
0.00
AC:
0
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152086
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74314
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41410
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68012
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Merosin deficient congenital muscular dystrophy Pathogenic:1
Dec 28, 2023
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
May 24, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PP3, PM2, PM3_strong, PM5, PS4_moderate -

Merosin deficient congenital muscular dystrophy;C4748327:Muscular dystrophy, limb-girdle, autosomal recessive 23 Pathogenic:1
Jun 13, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

LAMA2-related muscular dystrophy Uncertain:1
Sep 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with tyrosine, which is neutral and polar, at codon 146 of the LAMA2 protein (p.Ser146Tyr). This variant is present in population databases (no rsID available, gnomAD 0.004%). This missense change has been observed in individual(s) with clinical features of LAMA2-related conditions (PMID: 31130284). ClinVar contains an entry for this variant (Variation ID: 1431679). 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. 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
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.26
D
BayesDel_noAF
Uncertain
0.13
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Benign
0.067
.;T;T
Eigen
Pathogenic
0.83
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;D;D
M_CAP
Benign
0.073
D
MetaRNN
Pathogenic
0.87
D;D;D
MetaSVM
Uncertain
0.66
D
MutationAssessor
Pathogenic
3.9
.;.;H
PhyloP100
2.1
PrimateAI
Pathogenic
0.79
T
PROVEAN
Pathogenic
-4.8
.;.;D
REVEL
Pathogenic
0.83
Sift
Uncertain
0.0010
.;.;D
Polyphen
1.0
.;.;D
Vest4
0.83
MutPred
0.72
Loss of disorder (P = 0.0568);Loss of disorder (P = 0.0568);Loss of disorder (P = 0.0568);
MVP
0.93
MPC
0.54
ClinPred
1.0
D
GERP RS
5.0
Varity_R
0.91
gMVP
0.88
Mutation Taster
=34/66
disease causing

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: rs143680577; hg19: chr6-129419358; COSMIC: COSV70345971; API