6-129280072-C-T

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 2P and 9B. PM5BP4_StrongBP6BS2

The NM_000426.4(LAMA2):​c.2462C>T​(p.Thr821Met) variant causes a missense change. The variant allele was found at a frequency of 0.0023 in 1,612,224 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign 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. T821P) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0017 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0024 ( 10 hom. )

Consequence

LAMA2
NM_000426.4 missense

Scores

4
6
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:6

Conservation

PhyloP100: 3.64

Publications

18 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: Benign. The variant received -7 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr6-129280071-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 242608.Status of the report is criteria_provided_single_submitter, 1 stars.
BP4
Computational evidence support a benign effect (MetaRNN=0.055688918).
BP6
Variant 6-129280072-C-T is Benign according to our data. Variant chr6-129280072-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 162584.
BS2
High Homozygotes in GnomAdExome4 at 10 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA2NM_000426.4 linkc.2462C>T p.Thr821Met missense_variant Exon 18 of 65 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkc.2462C>T p.Thr821Met missense_variant Exon 18 of 64 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkc.2462C>T p.Thr821Met missense_variant Exon 18 of 65 5 NM_000426.4 ENSP00000400365.2 P24043
LAMA2ENST00000618192.5 linkc.2462C>T p.Thr821Met missense_variant Exon 18 of 66 5 ENSP00000480802.2 A0A087WX80
LAMA2ENST00000617695.5 linkc.2462C>T p.Thr821Met missense_variant Exon 18 of 64 5 ENSP00000481744.2 A0A087WYF1

Frequencies

GnomAD3 genomes
AF:
0.00168
AC:
256
AN:
152172
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000458
Gnomad AMI
AF:
0.00110
Gnomad AMR
AF:
0.000655
Gnomad ASJ
AF:
0.000576
Gnomad EAS
AF:
0.000386
Gnomad SAS
AF:
0.00124
Gnomad FIN
AF:
0.00358
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00260
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.00193
AC:
485
AN:
251274
AF XY:
0.00183
show subpopulations
Gnomad AFR exome
AF:
0.000554
Gnomad AMR exome
AF:
0.000639
Gnomad ASJ exome
AF:
0.00119
Gnomad EAS exome
AF:
0.000598
Gnomad FIN exome
AF:
0.00370
Gnomad NFE exome
AF:
0.00274
Gnomad OTH exome
AF:
0.00114
GnomAD4 exome
AF:
0.00237
AC:
3457
AN:
1459934
Hom.:
10
Cov.:
30
AF XY:
0.00231
AC XY:
1676
AN XY:
726406
show subpopulations
African (AFR)
AF:
0.000329
AC:
11
AN:
33416
American (AMR)
AF:
0.000807
AC:
36
AN:
44610
Ashkenazi Jewish (ASJ)
AF:
0.000843
AC:
22
AN:
26112
East Asian (EAS)
AF:
0.00121
AC:
48
AN:
39686
South Asian (SAS)
AF:
0.00116
AC:
100
AN:
86242
European-Finnish (FIN)
AF:
0.00341
AC:
182
AN:
53410
Middle Eastern (MID)
AF:
0.00174
AC:
10
AN:
5760
European-Non Finnish (NFE)
AF:
0.00265
AC:
2939
AN:
1110382
Other (OTH)
AF:
0.00181
AC:
109
AN:
60316
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.442
Heterozygous variant carriers
0
176
352
527
703
879
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
104
208
312
416
520
<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:
0.00167
AC:
255
AN:
152290
Hom.:
0
Cov.:
32
AF XY:
0.00158
AC XY:
118
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.000457
AC:
19
AN:
41570
American (AMR)
AF:
0.000654
AC:
10
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.000576
AC:
2
AN:
3472
East Asian (EAS)
AF:
0.000387
AC:
2
AN:
5174
South Asian (SAS)
AF:
0.00104
AC:
5
AN:
4828
European-Finnish (FIN)
AF:
0.00358
AC:
38
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00260
AC:
177
AN:
68018
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
12
23
35
46
58
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
4
8
12
16
20
<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:
0.00234
Hom.:
1
Bravo
AF:
0.00129
TwinsUK
AF:
0.00162
AC:
6
ALSPAC
AF:
0.00441
AC:
17
ESP6500AA
AF:
0.00113
AC:
5
ESP6500EA
AF:
0.00302
AC:
26
ExAC
AF:
0.00203
AC:
246
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.00262
EpiControl
AF:
0.00261

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:6
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:3
Jun 22, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 03, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 24611677, 24082139, 27896284, 23891399) -

Sep 13, 2023
Revvity Omics, Revvity
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

LAMA2: PM5, BP4, BS2 -

Merosin deficient congenital muscular dystrophy;C4748327:Muscular dystrophy, limb-girdle, autosomal recessive 23 Uncertain:2
Oct 27, 2021
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Jun 18, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1Benign:1
Sep 24, 2016
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 29, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: LAMA2 c.2462C>T (p.Thr821Met) results in a non-conservative amino acid change located in the EGF-like domain (IPR000742) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.002 in 282674 control chromosomes, predominantly at a frequency of 0.0036 within the Finnish subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within Finnish control individuals in the gnomAD database is approximately two fold of the estimated maximal expected allele frequency for a pathogenic variant in LAMA2 causing Laminin Alpha 2-Related Dystrophy phenotype (0.0022), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Finnish origin. c.2462C>T has been reported in the literature in at least two homozygous individuals affected with Laminin Alpha 2-Related Dystrophy (example Xiong_2015, Ge_2019, Tan_2021). However, these reports do not provide unequivocal evidence for an association of the variant with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Eight clinical-significance assessments for this variant have been submitted to ClinVar after 2014 with conflicting assessments (VUS n=5, likely benign n=2, benign n=1). Based on the evidence outlined above, the variant was classified as likely benign. -

Merosin deficient congenital muscular dystrophy Uncertain:1
Nov 25, 2017
Counsyl
Significance:Uncertain significance
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. -

Congenital muscular dystrophy due to partial LAMA2 deficiency Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

LAMA2-related muscular dystrophy Benign:1
Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Intellectual disability Benign:1
Jan 01, 2019
Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
-0.30
T
BayesDel_noAF
Benign
-0.21
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.062
.;T;T
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.24
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.78
T;T;T
M_CAP
Pathogenic
0.53
D
MetaRNN
Benign
0.056
T;T;T
MetaSVM
Uncertain
-0.061
T
MutationAssessor
Pathogenic
3.8
.;.;H
PhyloP100
3.6
PrimateAI
Benign
0.30
T
PROVEAN
Pathogenic
-4.5
.;.;D
REVEL
Uncertain
0.54
Sift
Pathogenic
0.0
.;.;D
Polyphen
1.0
.;.;D
Vest4
0.56
MVP
0.85
MPC
0.47
ClinPred
0.080
T
GERP RS
4.0
Varity_R
0.76
gMVP
0.40
Mutation Taster
=62/38
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.10
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: rs117422805; hg19: chr6-129601217; COSMIC: COSV108251554; API