18-23907639-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_198129.4(LAMA3):​c.6808C>T​(p.Arg2270*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000174 in 1,613,150 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

LAMA3
NM_198129.4 stop_gained

Scores

2
4
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 4.08
Variant links:
Genes affected
LAMA3 (HGNC:6483): (laminin subunit alpha 3) The protein encoded by this gene belongs to the laminin family of secreted molecules. Laminins are heterotrimeric molecules that consist of alpha, beta, and gamma subunits that assemble through a coiled-coil domain. Laminins are essential for formation and function of the basement membrane and have additional functions in regulating cell migration and mechanical signal transduction. This gene encodes an alpha subunit and is responsive to several epithelial-mesenchymal regulators including keratinocyte growth factor, epidermal growth factor and insulin-like growth factor. Mutations in this gene have been identified as the cause of Herlitz type junctional epidermolysis bullosa and laryngoonychocutaneous syndrome. Alternative splicing and alternative promoter usage result in multiple transcript variants. [provided by RefSeq, Dec 2014]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 18-23907639-C-T is Pathogenic according to our data. Variant chr18-23907639-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 8792.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA3NM_198129.4 linkc.6808C>T p.Arg2270* stop_gained Exon 53 of 75 ENST00000313654.14 NP_937762.2 Q16787-2
LAMA3NM_000227.6 linkc.1981C>T p.Arg661* stop_gained Exon 16 of 38 ENST00000269217.11 NP_000218.3 Q16787-1A0A0A6YYF2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA3ENST00000313654.14 linkc.6808C>T p.Arg2270* stop_gained Exon 53 of 75 1 NM_198129.4 ENSP00000324532.8 Q16787-2
LAMA3ENST00000269217.11 linkc.1981C>T p.Arg661* stop_gained Exon 16 of 38 1 NM_000227.6 ENSP00000269217.5 Q16787-1A0A0A6YYF2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152200
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
GnomAD3 exomes
AF:
0.00000795
AC:
2
AN:
251486
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135916
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000185
AC:
27
AN:
1460950
Hom.:
0
Cov.:
31
AF XY:
0.0000165
AC XY:
12
AN XY:
726844
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000207
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152200
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74362
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000611
Hom.:
0
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Junctional epidermolysis bullosa gravis of Herlitz Pathogenic:1
Dec 09, 2019
Myriad Genetics, Inc.
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

NM_000227.3(LAMA3):c.1981C>T(R661*) is classified as pathogenic in the context of LAMA3-related junctional epidermolysis bullosa. Sources cited for classification include the following: PMID 8824879, 8618022, 8530087 and 8983017. Classification of NM_000227.3(LAMA3):c.1981C>T(R661*) is based on the following criteria: The variant causes a premature termination codon that is expected to be targeted by nonsense-mediated mRNA decay and is reported in individuals with the relevant phenotype. Please note: this variant was assessed in the context of healthy population screening. -

not provided Pathogenic:1
Mar 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg661*) in the LAMA3 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LAMA3 are known to be pathogenic (PMID: 10366601, 11810295, 12915477, 16473856, 17362460, 22434185, 23869449, 27827380, 28087116). This variant is present in population databases (rs137852757, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with autosomal recessive junctional epidermolysis bullosa (PMID: 8530087). This variant is also known as R650X. ClinVar contains an entry for this variant (Variation ID: 8792). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Epidermolysis bullosa, junctional 2B, severe Pathogenic:1
Apr 01, 1996
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Laryngo-onycho-cutaneous syndrome;C5676936:Epidermolysis bullosa, junctional 2A, intermediate;C5676937:Epidermolysis bullosa, junctional 2B, severe Pathogenic:1
Jun 06, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.39
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Uncertain
0.68
Eigen_PC
Uncertain
0.49
FATHMM_MKL
Uncertain
0.85
D
Vest4
0.86
GERP RS
5.3

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs137852757; hg19: chr18-21487603; API