rs146931108

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1PP3_Moderate

The NM_000080.4(CHRNE):​c.581T>C​(p.Ile194Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00037 in 1,614,082 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a pathogenic 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. I194F) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00043 ( 1 hom., cov: 33)
Exomes 𝑓: 0.00036 ( 1 hom. )

Consequence

CHRNE
NM_000080.4 missense

Scores

6
9
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: 5.48

Publications

5 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]
C17orf107 (HGNC:37238): (chromosome 17 open reading frame 107)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 9 uncertain in NM_000080.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.849

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNENM_000080.4 linkc.581T>C p.Ile194Thr missense_variant Exon 6 of 12 ENST00000649488.2 NP_000071.1
C17orf107NM_001145536.2 linkc.*1012A>G 3_prime_UTR_variant Exon 3 of 3 ENST00000381365.4 NP_001139008.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNEENST00000649488.2 linkc.581T>C p.Ile194Thr missense_variant Exon 6 of 12 NM_000080.4 ENSP00000497829.1
C17orf107ENST00000381365.4 linkc.*1012A>G 3_prime_UTR_variant Exon 3 of 3 2 NM_001145536.2 ENSP00000370770.3

Frequencies

GnomAD3 genomes
AF:
0.000427
AC:
65
AN:
152102
Hom.:
1
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00131
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:
0.000618
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000256
AC:
64
AN:
250474
AF XY:
0.000281
show subpopulations
Gnomad AFR exome
AF:
0.000185
Gnomad AMR exome
AF:
0.000260
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000452
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000364
AC:
532
AN:
1461862
Hom.:
1
Cov.:
32
AF XY:
0.000342
AC XY:
249
AN XY:
727238
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000291
AC:
13
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000448
AC:
498
AN:
1111992
Other (OTH)
AF:
0.000331
AC:
20
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
28
55
83
110
138
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.000427
AC:
65
AN:
152220
Hom.:
1
Cov.:
33
AF XY:
0.000484
AC XY:
36
AN XY:
74430
show subpopulations
African (AFR)
AF:
0.0000722
AC:
3
AN:
41536
American (AMR)
AF:
0.00131
AC:
20
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000618
AC:
42
AN:
67984
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000472
Hom.:
0
Bravo
AF:
0.000438
ESP6500AA
AF:
0.000454
AC:
2
ESP6500EA
AF:
0.000465
AC:
4
ExAC
AF:
0.000288
AC:
35
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.000491
EpiControl
AF:
0.00101

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Congenital myasthenic syndrome 4A Uncertain:2
Jan 15, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 194 of the CHRNE protein (p.Ile194Thr). This variant is present in population databases (rs146931108, gnomAD 0.05%). 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: 534259). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on CHRNE protein function. 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. -

Feb 21, 2018
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

Congenital myasthenic syndrome Uncertain:2
Jan 24, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not specified Uncertain:1
Jun 06, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: CHRNE c.581T>C (p.Ile194Thr) results in a non-conservative amino acid change located in the Neurotransmitter-gated ion-channel ligand-binding domain (IPR006202) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00026 in 250474 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in CHRNE causing Congenital Myasthenic Syndrome (0.00026 vs 0.0025), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.581T>C in individuals affected with Congenital Myasthenic Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Inborn genetic diseases Uncertain:1
Sep 14, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.581T>C (p.I194T) alteration is located in exon 6 (coding exon 6) of the CHRNE gene. This alteration results from a T to C substitution at nucleotide position 581, causing the isoleucine (I) at amino acid position 194 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Congenital myasthenic syndrome 4C;C4225369:Congenital myasthenic syndrome 4B;C4225413:Congenital myasthenic syndrome 4A Uncertain:1
May 27, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
May 10, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.23
BayesDel_addAF
Benign
0.0094
T
BayesDel_noAF
Uncertain
0.11
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.68
D;D
Eigen
Uncertain
0.43
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.78
.;T
M_CAP
Pathogenic
0.52
D
MetaRNN
Pathogenic
0.85
D;D
MetaSVM
Uncertain
0.53
D
MutationAssessor
Uncertain
2.8
M;M
PhyloP100
5.5
PrimateAI
Uncertain
0.55
T
PROVEAN
Pathogenic
-4.7
D;.
REVEL
Pathogenic
0.81
Sift
Uncertain
0.0010
D;.
Sift4G
Pathogenic
0.0010
D;.
Polyphen
0.61
P;P
Vest4
0.76
MVP
0.93
MPC
0.69
ClinPred
0.85
D
GERP RS
4.6
Varity_R
0.74
gMVP
0.88
Mutation Taster
=61/39
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs146931108; hg19: chr17-4804840; COSMIC: COSV53418043; COSMIC: COSV53418043; API