rs780022652

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_ModeratePM2

The NM_001164508.2(NEB):​c.3987+1G>T variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.000036 in 1,612,620 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

NEB
NM_001164508.2 splice_donor, intron

Scores

5
1
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 5.54
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.0042223786 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.3, offset of 17, new splice context is: tagGTgaag. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NEBNM_001164507.2 linkc.3987+1G>T splice_donor_variant, intron_variant Intron 36 of 181 ENST00000427231.7 NP_001157979.2
NEBNM_001164508.2 linkc.3987+1G>T splice_donor_variant, intron_variant Intron 36 of 181 ENST00000397345.8 NP_001157980.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NEBENST00000397345.8 linkc.3987+1G>T splice_donor_variant, intron_variant Intron 36 of 181 5 NM_001164508.2 ENSP00000380505.3 P20929-2
NEBENST00000427231.7 linkc.3987+1G>T splice_donor_variant, intron_variant Intron 36 of 181 5 NM_001164507.2 ENSP00000416578.2 P20929-3
NEBENST00000409198.5 linkc.3987+1G>T splice_donor_variant, intron_variant Intron 36 of 149 5 ENSP00000386259.1 P20929-4

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152248
Hom.:
0
Cov.:
31
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000160
AC:
4
AN:
249226
Hom.:
0
AF XY:
0.00000740
AC XY:
1
AN XY:
135202
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:
0.0000265
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000363
AC:
53
AN:
1460372
Hom.:
0
Cov.:
29
AF XY:
0.0000358
AC XY:
26
AN XY:
726592
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
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:
0.0000423
Gnomad4 OTH exome
AF:
0.0000829
GnomAD4 genome
AF:
0.0000328
AC:
5
AN:
152248
Hom.:
0
Cov.:
31
AF XY:
0.0000269
AC XY:
2
AN XY:
74380
show subpopulations
Gnomad4 AFR
AF:
0.00
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:
0.0000735
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000151
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

Nemaline myopathy Pathogenic:1
Mar 18, 2025
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

The c.3987+1G>T variant in NEB has not been previously reported in the literature in individuals with nemaline myopathy, but has been identified in 0.004% (52/1178690) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs780022652). 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 is located in the 5' splice region. SpliceAI predictions indicate use of an out-of-frame cryptic splice site 17 bases from the intron-exon boundary, providing evidence that this variant may cause a frameshift and lead to a premature termination codon downstream. This alteration is then predicted to lead to a truncated or absent protein. However, this information is not predictive enough to determine pathogenicity. One additional pathogenic variant, predicted to induce the same splicing effect as this variant, has been reported in ClinVar as being associated with nemaline myopathy, supporting that the c.3987+1G>T variant may be pathogenic (Variation ID: 371210). In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive nemaline myopathy. ACMG/AMP Criteria applied: PVS1, PM2_Supporting, PS1_supporting (Richards 2015). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.40
CADD
Pathogenic
35
DANN
Uncertain
0.99
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.99
FATHMM_MKL
Pathogenic
0.98
D
GERP RS
5.4

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_DG_spliceai
0.68
Position offset: -16
DS_DL_spliceai
1.0
Position offset: 1

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: rs780022652; hg19: chr2-152530990; API