1-209632678-G-A

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_000228.3(LAMB3):​c.727C>T​(p.Gln243*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,614,096 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

LAMB3
NM_000228.3 stop_gained

Scores

3
3
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 2.40

Publications

6 publications found
Variant links:
Genes affected
LAMB3 (HGNC:6490): (laminin subunit beta 3) The product encoded by this gene is a laminin that belongs to a family of basement membrane proteins. This protein is a beta subunit laminin, which together with an alpha and a gamma subunit, forms laminin-5. Mutations in this gene cause epidermolysis bullosa junctional Herlitz type, and generalized atrophic benign epidermolysis bullosa, diseases that are characterized by blistering of the skin. Multiple alternatively spliced transcript variants that encode the same protein have been found for this gene. [provided by RefSeq, Jul 2008]
LAMB3 Gene-Disease associations (from GenCC):
  • junctional epidermolysis bullosa
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • junctional epidermolysis bullosa Herlitz type
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, Laboratory for Molecular Medicine
  • junctional epidermolysis bullosa, non-Herlitz type
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Genomics England PanelApp, Ambry Genetics
  • amelogenesis imperfecta type 1A
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • amelogenesis imperfecta type 1
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • generalized junctional epidermolysis bullosa non-Herlitz type
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 1-209632678-G-A is Pathogenic according to our data. Variant chr1-209632678-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 35480.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
LAMB3NM_000228.3 linkc.727C>T p.Gln243* stop_gained Exon 8 of 23 ENST00000356082.9 NP_000219.2 Q13751A0A0S2Z3R6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMB3ENST00000356082.9 linkc.727C>T p.Gln243* stop_gained Exon 8 of 23 1 NM_000228.3 ENSP00000348384.3 Q13751
LAMB3ENST00000367030.7 linkc.727C>T p.Gln243* stop_gained Exon 8 of 23 1 ENSP00000355997.3 Q13751
LAMB3ENST00000391911.5 linkc.727C>T p.Gln243* stop_gained Exon 7 of 22 1 ENSP00000375778.1 Q13751

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152224
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251416
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000280
AC:
41
AN:
1461872
Hom.:
0
Cov.:
32
AF XY:
0.0000303
AC XY:
22
AN XY:
727236
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000351
AC:
39
AN:
1111994
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
3
6
8
11
14
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:
0.0000460
AC:
7
AN:
152224
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74378
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
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

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:
0.0000338
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:4
Dec 11, 2023
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.Gln243*) in the LAMB3 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LAMB3 are known to be pathogenic (PMID: 11023379, 16473856). This variant is present in population databases (rs80356681, gnomAD 0.008%). This premature translational stop signal has been observed in individuals with junctional epidermolysis bullosa (PMID: 8824879, 9326326). ClinVar contains an entry for this variant (Variation ID: 35480). 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. -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Sep 13, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 25525159, 34426522, 34582790, 17000025, 27913086, 9326326, 8824879) -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

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

NM_000228.2(LAMB3):c.727C>T(Q243*) is classified as likely pathogenic in the context of Herlitz junctional epidermolysis bullosa, LAMB3-related. Sources cited for classification include the following: PMID 11023379, 8983017, 12813757, 16473856, 9326326 and 8824879. Classification of NM_000228.2(LAMB3):c.727C>T(Q243*) 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. -

-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Junctional epidermolysis bullosa gravis of Herlitz;C0268374:Junctional epidermolysis bullosa, non-Herlitz type;C4011403:Amelogenesis imperfecta type 1A Pathogenic:1
May 03, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Junctional epidermolysis bullosa Pathogenic:1
Jun 08, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: LAMB3 c.727C>T (p.Gln243X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 8e-06 in 251416 control chromosomes (gnomAD). c.727C>T has been reported in the literature, in the compound heterozygous or homozygous state, in multiple individuals affected with Junctional Epidermolysis Bullosa (e.g. Hammersen_2016, Kivirikko_1996, Pfender_2003, Robbins_2001). These data indicate that the variant is very likely to be associated with disease. Four ClinVar submitters (evaluation after 2014) cite the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.55
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
37
DANN
Uncertain
1.0
Eigen
Pathogenic
0.84
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Uncertain
0.89
D
PhyloP100
2.4
Vest4
0.58
GERP RS
4.8
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.21
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.21
Position offset: -3

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

Publications

Other links and lift over

dbSNP: rs80356681; hg19: chr1-209806023; API