rs545937015

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PVS1_ModeratePM2PP5

The NM_001164508.2(NEB):​c.23742+2T>C variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.0000639 in 1,612,912 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000065 ( 0 hom. )

Consequence

NEB
NM_001164508.2 splice_donor, intron

Scores

4
2
1
Splicing: ADA: 0.9995
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:8U:1

Conservation

PhyloP100: 5.95
Variant links:
Genes affected
NEB (HGNC:7720): (nebulin) This gene encodes nebulin, a giant protein component of the cytoskeletal matrix that coexists with the thick and thin filaments within the sarcomeres of skeletal muscle. In most vertebrates, nebulin accounts for 3 to 4% of the total myofibrillar protein. The encoded protein contains approximately 30-amino acid long modules that can be classified into 7 types and other repeated modules. Protein isoform sizes vary from 600 to 800 kD due to alternative splicing that is tissue-, species-,and developmental stage-specific. Of the 183 exons in the nebulin gene, at least 43 are alternatively spliced, although exons 143 and 144 are not found in the same transcript. Of the several thousand transcript variants predicted for nebulin, the RefSeq Project has decided to create three representative RefSeq records. Mutations in this gene are associated with recessive nemaline myopathy. [provided by RefSeq, Sep 2009]
RIF1 (HGNC:23207): (replication timing regulatory factor 1) This gene encodes a protein that shares homology with the yeast teleomere binding protein, Rap1 interacting factor 1. This protein localizes to aberrant telomeres may be involved in DNA repair. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Apr 2010]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.003635937 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 2-151505476-A-G is Pathogenic according to our data. Variant chr2-151505476-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 375408.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=6, Uncertain_significance=1}. Variant chr2-151505476-A-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NEBNM_001164507.2 linkc.23742+2T>C splice_donor_variant, intron_variant Intron 165 of 181 ENST00000427231.7 NP_001157979.2
NEBNM_001164508.2 linkc.23742+2T>C splice_donor_variant, intron_variant Intron 165 of 181 ENST00000397345.8 NP_001157980.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NEBENST00000397345.8 linkc.23742+2T>C splice_donor_variant, intron_variant Intron 165 of 181 5 NM_001164508.2 ENSP00000380505.3 P20929-2
NEBENST00000427231.7 linkc.23742+2T>C splice_donor_variant, intron_variant Intron 165 of 181 5 NM_001164507.2 ENSP00000416578.2 P20929-3

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152170
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:
0.000103
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000281
AC:
7
AN:
249022
Hom.:
0
AF XY:
0.0000370
AC XY:
5
AN XY:
135060
show subpopulations
Gnomad AFR exome
AF:
0.0000646
Gnomad AMR exome
AF:
0.00
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:
0.0000532
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000650
AC:
95
AN:
1460742
Hom.:
0
Cov.:
30
AF XY:
0.0000688
AC XY:
50
AN XY:
726730
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000819
Gnomad4 OTH exome
AF:
0.0000663
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152170
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74346
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:
0.000103
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000772
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:8Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Nemaline myopathy 2 Pathogenic:3
Jun 27, 2016
Knight Diagnostic Laboratories, Oregon Health and Sciences University
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.23847+2T>C splice variant in the NEB gene has not been previously reported in patients and this variant is absent (1000 Genomes; Exome Sequencing Project) or reported at low frequency in the population databases (ExAC = 0.01%; only 2 alleles). Splice-site, nonsense, and frameshift variants have been described in the NEB gene in multiple affected individuals (including nonsense and frameshift variants downstream of this variant) and thus, loss of function is a known mechanism of disease (GeneReviews: North and Ryan, 2015). Multiple in silico algorithms show high evolutionary conservation (CADD = 18.14; GERP=5.48), and in silico splicing algorithms predict this variant will cause altered splicing (Human Splice Finder=Broken WT Donor Site; SPIDEX=-3.228). Therefore, this collective evidence supports the classification of the c.23847+2T>C variant as a Likely pathogenic variant for Nemaline Myopathy 2. We have confirmed this finding in our laboratory using Sanger sequencing. -

Dec 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change affects a donor splice site in intron 166 of the NEB gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in NEB are known to be pathogenic (PMID: 25205138). This variant is present in population databases (rs545937015, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with NEB-related conditions. ClinVar contains an entry for this variant (Variation ID: 375408). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Sep 16, 2020
Natera, Inc.
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Pathogenic:2
Nov 24, 2019
Revvity Omics, Revvity
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 09, 2024
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported as a single heterozygous variant in an individual undergoing preconception carrier screening (PMID: 29754767); Canonical splice site variant predicted to result in an in-frame loss of the adjacent exon in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Deletions involving coding exons of this gene are a known mechanism of disease (HGMD); This variant is associated with the following publications: (PMID: 31589614, 29754767) -

Nemaline myopathy Pathogenic:1
Feb 28, 2025
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

The c.23742+2T>C variant in NEB has not been previously reported in the literature in individuals with nemaline myopathy, but has been identified in 0.008% (98/1179056) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs545937015). Although this variant has been seen in the general population in a heterozygous state, its frequency is low enough to be consistent with a recessive carrier frequency. This variant has also been reported in ClinVar (Variation ID: 375408) and has been interpreted as likely pathogenic by Knight Diagnostic Laboratories (Oregon Health and Sciences University), Invitae, PerkinElmer Genomics, and Natera Inc., and as a variant of uncertain significance by the Laboratory for Molecular Medicine (Mass General Brigham Personalized Medicine). This variant is located in the 5' splice region. Computational tools predict a splicing impact, though this information is not predictive enough to determine pathogenicity. Loss of function of the NEB gene is an established disease mechanism in autosomal recessive nemaline myopathy. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal recessive nemaline myopathy. ACMG/AMP Criteria applied: PVS1, PM2_supporting (Richards 2015). -

Arthrogryposis multiplex congenita 6 Pathogenic:1
Feb 26, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nemaline myopathy 2;C5543431:Arthrogryposis multiplex congenita 6 Pathogenic:1
Apr 22, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Uncertain:1
Jul 25, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The c.23847+2T>C variant in NEB has not been previously reported in individuals with myopathy but has been identified in 0.008% (10/128308) of European chromosomes by gnomAD (http://gnomad.broadinstitute.org). This variant has been reported in ClinVar (Variation ID: 375408). This variant occurs within the canonical splice site (+/- 1,2), but splicing predictors do not predict a significant change in splicing and the exons surrounding this variant are in-frame. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PVS1_Moderate, PMS2 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.27
CADD
Pathogenic
29
DANN
Uncertain
0.99
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.92
FATHMM_MKL
Uncertain
0.97
D
GERP RS
5.5

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.84
SpliceAI score (max)
0.98
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.98
Position offset: 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: rs545937015; hg19: chr2-152361990; COSMIC: COSV105847693; COSMIC: COSV105847693; API