6-129393042-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_000426.4(LAMA2):​c.5235-3C>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,612,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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 (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

LAMA2
NM_000426.4 splice_region, intron

Scores

2
Splicing: ADA: 0.5724
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.536

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: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.63).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA2NM_000426.4 linkc.5235-3C>T splice_region_variant, intron_variant Intron 36 of 64 ENST00000421865.3 NP_000417.3
LAMA2NM_001079823.2 linkc.5235-3C>T splice_region_variant, intron_variant Intron 36 of 63 NP_001073291.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA2ENST00000421865.3 linkc.5235-3C>T splice_region_variant, intron_variant Intron 36 of 64 5 NM_000426.4 ENSP00000400365.2
LAMA2ENST00000618192.5 linkc.5499-3C>T splice_region_variant, intron_variant Intron 37 of 65 5 ENSP00000480802.2
LAMA2ENST00000617695.5 linkc.5235-3C>T splice_region_variant, intron_variant Intron 36 of 63 5 ENSP00000481744.2
LAMA2ENST00000687590.1 linkn.1655-3C>T splice_region_variant, intron_variant Intron 4 of 4

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152006
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000121
AC:
3
AN:
248170
AF XY:
0.0000149
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000550
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000178
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000685
AC:
10
AN:
1460158
Hom.:
0
Cov.:
30
AF XY:
0.00000413
AC XY:
3
AN XY:
726492
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33452
American (AMR)
AF:
0.00
AC:
0
AN:
44696
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39688
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86242
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52564
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5722
European-Non Finnish (NFE)
AF:
0.00000810
AC:
9
AN:
1111304
Other (OTH)
AF:
0.00
AC:
0
AN:
60362
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.445
Heterozygous variant carriers
0
1
2
2
3
4
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:
152006
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74238
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41358
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10574
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
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
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

LAMA2-related muscular dystrophy Uncertain:1
Sep 13, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 36 of the LAMA2 gene. It does not directly change the encoded amino acid sequence of the LAMA2 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs761823344, gnomAD 0.006%). 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: 1359409). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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
BayesDel_noAF
Benign
-0.63
CADD
Benign
9.5
DANN
Benign
0.54
PhyloP100
0.54

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.57
dbscSNV1_RF
Benign
0.45
SpliceAI score (max)
0.020
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: rs761823344; hg19: chr6-129714187; API