chr6-129192680-A-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000426.4(LAMA2):​c.1609A>T​(p.Ile537Leu) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/24 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. I537I) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 missense, splice_region

Scores

3
15
Splicing: ADA: 0.1438
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.72

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: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.18677735).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA2NM_000426.4 linkc.1609A>T p.Ile537Leu missense_variant, splice_region_variant Exon 12 of 65 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkc.1609A>T p.Ile537Leu missense_variant, splice_region_variant Exon 12 of 64 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkc.1609A>T p.Ile537Leu missense_variant, splice_region_variant Exon 12 of 65 5 NM_000426.4 ENSP00000400365.2 P24043

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152166
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
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:
251464
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
1461598
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727118
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111740
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000657
AC:
1
AN:
152284
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74458
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41564
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

LAMA2-related muscular dystrophy Uncertain:1
Oct 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 537 of the LAMA2 protein (p.Ile537Leu). This variant is present in population databases (rs148262047, gnomAD 0.007%). 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: 567365). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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
Benign
0.12
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.39
CADD
Benign
18
DANN
Uncertain
0.98
DEOGEN2
Benign
0.029
.;T;T
Eigen
Benign
-0.14
Eigen_PC
Benign
-0.0053
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.66
T;T;T
M_CAP
Benign
0.011
T
MetaRNN
Benign
0.19
T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.7
.;.;L
PhyloP100
1.7
PrimateAI
Benign
0.44
T
PROVEAN
Benign
-1.7
.;.;N
REVEL
Benign
0.067
Sift
Uncertain
0.022
.;.;D
Polyphen
0.048
.;.;B
Vest4
0.48
MutPred
0.51
Loss of methylation at K536 (P = 0.0646);Loss of methylation at K536 (P = 0.0646);Loss of methylation at K536 (P = 0.0646);
MVP
0.48
MPC
0.088
ClinPred
0.30
T
GERP RS
4.3
Varity_R
0.19
gMVP
0.55
Mutation Taster
=76/24
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.14
dbscSNV1_RF
Benign
0.17
SpliceAI score (max)
0.040
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: rs148262047; hg19: chr6-129513825; API