chr17-4898873-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_000080.4(CHRNE):​c.1345C>A​(p.Arg449Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000699 in 1,430,516 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R449C) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 7.0e-7 ( 0 hom. )

Consequence

CHRNE
NM_000080.4 missense

Scores

4
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.33

Publications

1 publications found
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]
CHRNE Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome
    Inheritance: AR Classification: DEFINITIVE Submitted by: Illumina
  • congenital myasthenic syndrome 4A
    Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
  • congenital myasthenic syndrome 4B
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
  • congenital myasthenic syndrome 4C
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
  • postsynaptic congenital myasthenic syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.3242401).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000080.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNE
NM_000080.4
MANE Select
c.1345C>Ap.Arg449Ser
missense
Exon 12 of 12NP_000071.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNE
ENST00000649488.2
MANE Select
c.1345C>Ap.Arg449Ser
missense
Exon 12 of 12ENSP00000497829.1
CHRNE
ENST00000649830.1
c.521C>Ap.Ala174Glu
missense
Exon 11 of 11ENSP00000496907.1
CHRNE
ENST00000572438.1
TSL:5
n.1031C>A
non_coding_transcript_exon
Exon 7 of 7

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000103
AC:
2
AN:
195048
AF XY:
0.0000191
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000680
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.99e-7
AC:
1
AN:
1430516
Hom.:
0
Cov.:
34
AF XY:
0.00000141
AC XY:
1
AN XY:
708734
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33064
American (AMR)
AF:
0.00
AC:
0
AN:
38530
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25438
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38498
South Asian (SAS)
AF:
0.0000122
AC:
1
AN:
82172
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50878
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5726
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1096900
Other (OTH)
AF:
0.00
AC:
0
AN:
59310
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
ExAC
AF:
0.00000832
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Congenital myasthenic syndrome 4A Uncertain:1
Jan 14, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 449 of the CHRNE protein (p.Arg449Ser). 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. This variant has not been reported in the literature in individuals affected with CHRNE-related conditions. ClinVar contains an entry for this variant (Variation ID: 959504). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CHRNE protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

not provided Uncertain:1
May 19, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge

Congenital myasthenic syndrome Uncertain:1
May 17, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.23
BayesDel_addAF
Uncertain
0.066
T
BayesDel_noAF
Benign
-0.14
CADD
Uncertain
24
DANN
Uncertain
0.99
Eigen
Benign
-0.031
Eigen_PC
Benign
0.079
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Benign
0.18
T
M_CAP
Uncertain
0.087
D
MetaRNN
Benign
0.32
T
PhyloP100
2.3
ClinPred
0.70
D
GERP RS
4.0
Varity_R
0.44

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.20
Details are displayed if max score is > 0.2
DS_AL_spliceai
0.20
Position offset: 18

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

Publications

Other links and lift over

dbSNP: rs149083639; hg19: chr17-4802168; API