chr17-4899386-T-A

Variant summary

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

The NM_000080.4(CHRNE):​c.1033-2A>T variant causes a splice acceptor change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000326 in 1,533,780 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: 33)
Exomes 𝑓: 0.0000029 ( 0 hom. )

Consequence

CHRNE
NM_000080.4 splice_acceptor

Scores

2
2
3
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 2.98
Variant links:
Genes affected
CHRNE (HGNC:1966): (cholinergic receptor nicotinic epsilon subunit) Acetylcholine receptors at mature mammalian neuromuscular junctions are pentameric protein complexes composed of four subunits in the ratio of two alpha subunits to one beta, one epsilon, and one delta subunit. The acetylcholine receptor changes subunit composition shortly after birth when the epsilon subunit replaces the gamma subunit seen in embryonic receptors. Mutations in the epsilon subunit are associated with congenital myasthenic syndrome. [provided by RefSeq, Sep 2009]
C17orf107 (HGNC:37238): (chromosome 17 open reading frame 107)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 17-4899386-T-A is Pathogenic according to our data. Variant chr17-4899386-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 189225.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CHRNENM_000080.4 linkuse as main transcriptc.1033-2A>T splice_acceptor_variant ENST00000649488.2 NP_000071.1
CHRNEXM_017024115.2 linkuse as main transcriptc.997-2A>T splice_acceptor_variant XP_016879604.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CHRNEENST00000649488.2 linkuse as main transcriptc.1033-2A>T splice_acceptor_variant NM_000080.4 ENSP00000497829 P1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151992
Hom.:
0
Cov.:
33
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
GnomAD4 exome
AF:
0.00000289
AC:
4
AN:
1381788
Hom.:
0
Cov.:
35
AF XY:
0.00000293
AC XY:
2
AN XY:
681866
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:
0.00000279
Gnomad4 OTH exome
AF:
0.0000174
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
151992
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74244
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:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000112
Hom.:
0

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Congenital myasthenic syndrome 4A Pathogenic:2
Likely pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJun 06, 2023In 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. Studies have shown that disruption of this splice site is associated with altered splicing resulting in multiple RNA products (PMID: 14532324). ClinVar contains an entry for this variant (Variation ID: 189225). Disruption of this splice site has been observed in individual(s) with congenital myasthenic syndrome (PMID: 14532324). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change affects an acceptor splice site in intron 9 of the CHRNE 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 CHRNE are known to be pathogenic (PMID: 22678886). -
Likely pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsAug 05, 2023- -
Congenital myasthenic syndrome 4C Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineJul 16, 2014The 1033-2A>T variant in CHRNE has not been previously identified in individuals with congenital myasthenic syndrome. Data from large population studies is insufficient to assess the frequency of this variant. This variant occurs in the invariant region (+/- 1,2) of the splice consensus sequence and is predicted to cause altered splicing leading to an abnormal or absent protein. Additionally, other variants at this splice junction (1033-1G>A and 1033-1G>C) have been reported in individuals with congenital myasthenic syndrome (Ohno 2005). In summary, this variant meets our criteria to be classified as pathogenic (http://pcpgm.partners.org/LMM). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Benign
-0.090
CADD
Pathogenic
26
DANN
Benign
0.95
Eigen
Pathogenic
0.71
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Uncertain
0.94
D
MutationTaster
Benign
1.0
D
GERP RS
4.7

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.95
SpliceAI score (max)
0.99
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.30
Position offset: -14
DS_AL_spliceai
0.99
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: rs786204773; hg19: chr17-4802681; API