rs1060500981

Variant summary

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

The NM_001105206.3(LAMA4):​c.59C>T​(p.Ala20Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,612,398 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A20A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

LAMA4
NM_001105206.3 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 0.543

Publications

3 publications found
Variant links:
Genes affected
LAMA4 (HGNC:6484): (laminin subunit alpha 4) Laminins, a family of extracellular matrix glycoproteins, are the major noncollagenous constituent of basement membranes. They have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Laminins are composed of 3 non identical chains: laminin alpha, beta and gamma (formerly A, B1, and B2, respectively) and they form a cruciform structure consisting of 3 short arms, each formed by a different chain, and a long arm composed of all 3 chains. Each laminin chain is a multidomain protein encoded by a distinct gene. Several isoforms of each chain have been described. Different alpha, beta and gamma chain isomers combine to give rise to different heterotrimeric laminin isoforms which are designated by Arabic numerals in the order of their discovery, i.e. alpha1beta1gamma1 heterotrimer is laminin 1. The biological functions of the different chains and trimer molecules are largely unknown, but some of the chains have been shown to differ with respect to their tissue distribution, presumably reflecting diverse functions in vivo. This gene encodes the alpha chain isoform laminin, alpha 4. The domain structure of alpha 4 is similar to that of alpha 3, both of which resemble truncated versions of alpha 1 and alpha 2, in that approximately 1,200 residues at the N-terminus (domains IV, V and VI) have been lost. Laminin, alpha 4 contains the C-terminal G domain which distinguishes all alpha chains from the beta and gamma chains. The RNA analysis from adult and fetal tissues revealed developmental regulation of expression, however, the exact function of laminin, alpha 4 is not known. Tissue-specific utilization of alternative polyA-signal has been described in literature. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Aug 2011]
LAMA4-AS1 (HGNC:40333): (LAMA4 antisense RNA 1)

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=0.10247728).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA4NM_001105206.3 linkc.59C>T p.Ala20Val missense_variant Exon 2 of 39 ENST00000230538.12 NP_001098676.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA4ENST00000230538.12 linkc.59C>T p.Ala20Val missense_variant Exon 2 of 39 1 NM_001105206.3 ENSP00000230538.7
ENSG00000281613ENST00000587816.2 linkc.-398+17176G>A intron_variant Intron 1 of 4 5 ENSP00000487146.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152222
Hom.:
0
Cov.:
32
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
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1460176
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
726356
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44642
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26090
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86064
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52404
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111730
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60316
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
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:
152222
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74356
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
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

ClinVar

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

Submissions by phenotype

Dilated cardiomyopathy 1JJ Uncertain:1
Sep 01, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine with valine at codon 20 of the LAMA4 protein (p.Ala20Val). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and valine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with LAMA4-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. -

not provided Uncertain:1
Jun 06, 2016
Stanford Center for Inherited Cardiovascular Disease, Stanford University
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:provider interpretation

- -

Cardiovascular phenotype Uncertain:1
Apr 26, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A20V variant (also known as c.59C>T), located in coding exon 1 of the LAMA4 gene, results from a C to T substitution at nucleotide position 59. The alanine at codon 20 is replaced by valine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. The evidence for this gene-disease relationship is limited; therefore, the clinical significance of this alteration is unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.096
BayesDel_addAF
Benign
-0.14
T
BayesDel_noAF
Benign
-0.44
CADD
Benign
17
DANN
Uncertain
1.0
DEOGEN2
Benign
0.0080
T;T;T;T;.;T;.;.;T;.;.;.
Eigen
Benign
-0.74
Eigen_PC
Benign
-0.60
FATHMM_MKL
Benign
0.18
N
LIST_S2
Benign
0.78
T;.;.;T;T;T;T;T;T;.;.;T
M_CAP
Benign
0.0065
T
MetaRNN
Benign
0.10
T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.97
T
MutationAssessor
Benign
0.20
.;.;.;.;.;.;.;.;.;N;N;N
PhyloP100
0.54
PrimateAI
Benign
0.44
T
PROVEAN
Benign
0.48
N;N;N;N;N;N;N;N;N;N;N;N
REVEL
Benign
0.070
Sift
Benign
1.0
T;T;T;T;T;T;T;T;T;T;T;T
Sift4G
Benign
1.0
T;T;T;T;.;.;D;.;.;D;D;.
Polyphen
0.017, 0.0070
.;.;.;.;.;.;B;.;.;B;B;B
Vest4
0.12
MutPred
0.41
Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);Loss of disorder (P = 0.0893);
MVP
0.30
MPC
0.12
ClinPred
0.10
T
GERP RS
-0.30
PromoterAI
-0.11
Neutral
gMVP
0.49
Mutation Taster
=87/13
polymorphism

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: rs1060500981; hg19: chr6-112575294; API