rs746999970

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1_ModeratePP5_Very_Strong

The NM_001164507.2(NEB):​c.3879+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.0000077 in 1,558,560 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000078 ( 0 hom. )

Consequence

NEB
NM_001164507.2 splice_donor, intron

Scores

4
2
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 5.37

Publications

0 publications found
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]
NEB Gene-Disease associations (from GenCC):
  • nemaline myopathy 2
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, G2P, Ambry Genetics
  • childhood-onset nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • intermediate nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • typical nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • lethal multiple pterygium syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • severe congenital nemaline myopathy
    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 10 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.00410509 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PP5
Variant 2-151675286-C-T is Pathogenic according to our data. Variant chr2-151675286-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 554705.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
NEBNM_001164507.2 linkc.3879+1G>A splice_donor_variant, intron_variant Intron 35 of 181 ENST00000427231.7 NP_001157979.2
NEBNM_001164508.2 linkc.3879+1G>A splice_donor_variant, intron_variant Intron 35 of 181 ENST00000397345.8 NP_001157980.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NEBENST00000397345.8 linkc.3879+1G>A splice_donor_variant, intron_variant Intron 35 of 181 5 NM_001164508.2 ENSP00000380505.3 P20929-2
NEBENST00000427231.7 linkc.3879+1G>A splice_donor_variant, intron_variant Intron 35 of 181 5 NM_001164507.2 ENSP00000416578.2 P20929-3
NEBENST00000409198.5 linkc.3879+1G>A splice_donor_variant, intron_variant Intron 35 of 149 5 ENSP00000386259.1 P20929-4

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152120
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:
0.00000980
AC:
2
AN:
204144
AF XY:
0.00000920
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:
0.0000228
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000782
AC:
11
AN:
1406440
Hom.:
0
Cov.:
29
AF XY:
0.0000115
AC XY:
8
AN XY:
697626
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32454
American (AMR)
AF:
0.00
AC:
0
AN:
40024
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25414
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38744
South Asian (SAS)
AF:
0.0000247
AC:
2
AN:
81074
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51776
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5690
European-Non Finnish (NFE)
AF:
0.00000839
AC:
9
AN:
1072774
Other (OTH)
AF:
0.00
AC:
0
AN:
58490
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.434
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.00000657
AC:
1
AN:
152120
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74304
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41422
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
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:
2092
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
Alfa
AF:
0.0000312
Hom.:
0
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000166
AC:
2

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Nemaline myopathy 2 Pathogenic:3
Dec 31, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

May 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change affects a donor splice site in intron 35 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). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. Disruption of this splice site has been observed in individuals with nemaline myopathy who carry a second pathogenic variant (PMID: 25205138; Invitae). ClinVar contains an entry for this variant (Variation ID: 554705). 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. -

Nov 01, 2017
Counsyl
Significance:Likely pathogenic
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. -

Nemaline myopathy Pathogenic:1
Jan 27, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: NEB c.3879+1G>A is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing and loss of NEB function. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a canonical 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The frequency data for this variant in gnomAD is considered unreliable, as metrics indicate poor data quality at this position. c.3879+1G>A has been reported in the literature in individuals affected with Nemaline Myopathy 2 (examples: Lehtokari_2014, Khalaf_2024). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 25205138, 38438125). ClinVar contains an entry for this variant (Variation ID: 554705). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided Pathogenic:1
Oct 12, 2023
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported previously in a patient with nemaline myopathy who also harbored a second NEB variant; however phase was undetermined (Lehtokari et al., 2014); 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; Deletions involving coding exons in this gene are frequently reported as pathogenic, regardless of frame prediction (HGMD); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25205138, 24077912) -

Arthrogryposis multiplex congenita 6 Pathogenic:1
Mar 30, 2024
Baylor 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
0.37
CADD
Pathogenic
32
DANN
Uncertain
0.99
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.97
FATHMM_MKL
Uncertain
0.94
D
PhyloP100
5.4
GERP RS
5.5
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.94
SpliceAI score (max)
1.0
Details are displayed if max score is > 0.2
DS_DL_spliceai
1.0
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs746999970; hg19: chr2-152531800; COSMIC: COSV50830700; COSMIC: COSV50830700; API