rs376604413

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_000747.3(CHRNB1):​c.578A>G​(p.Gln193Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000235 in 1,614,112 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

CHRNB1
NM_000747.3 missense

Scores

2
16

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.81

Publications

0 publications found
Variant links:
Genes affected
CHRNB1 (HGNC:1961): (cholinergic receptor nicotinic beta 1 subunit) The muscle acetylcholine receptor is composed of five subunits: two alpha subunits and one beta, one gamma, and one delta subunit. This gene encodes the beta subunit of the acetylcholine receptor. The acetylcholine receptor changes conformation upon acetylcholine binding leading to the opening of an ion-conducting channel across the plasma membrane. Mutations in this gene are associated with slow-channel congenital myasthenic syndrome. [provided by RefSeq, Jul 2008]
CHRNB1 Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 2C
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • congenital myasthenic syndrome 1A
    Inheritance: AD Classification: STRONG Submitted by: PanelApp Australia
  • congenital myasthenic syndrome 2A
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
  • 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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.123286575).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB1NM_000747.3 linkc.578A>G p.Gln193Arg missense_variant Exon 6 of 11 ENST00000306071.7 NP_000738.2 P11230-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNB1ENST00000306071.7 linkc.578A>G p.Gln193Arg missense_variant Exon 6 of 11 1 NM_000747.3 ENSP00000304290.2 P11230-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152226
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251482
AF XY:
0.0000221
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:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000233
AC:
34
AN:
1461886
Hom.:
0
Cov.:
32
AF XY:
0.0000261
AC XY:
19
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000288
AC:
32
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000263
AC:
4
AN:
152226
Hom.:
0
Cov.:
31
AF XY:
0.0000134
AC XY:
1
AN XY:
74378
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000823
Hom.:
0
Bravo
AF:
0.0000227
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

Congenital myasthenic syndrome 2A Uncertain:1
Jul 26, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. 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 CHRNB1 protein function. ClinVar contains an entry for this variant (Variation ID: 570481). This variant has not been reported in the literature in individuals affected with CHRNB1-related conditions. This variant is present in population databases (rs376604413, gnomAD 0.004%). This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 193 of the CHRNB1 protein (p.Gln193Arg). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.064
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.43
CADD
Benign
15
DANN
Uncertain
0.98
DEOGEN2
Benign
0.13
T;.;.
Eigen
Benign
-0.48
Eigen_PC
Benign
-0.29
FATHMM_MKL
Uncertain
0.77
D
M_CAP
Benign
0.017
T
MetaRNN
Benign
0.12
T;T;T
MetaSVM
Benign
-0.95
T
MutationAssessor
Benign
-0.33
N;.;.
PhyloP100
1.8
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.84
N;N;.
REVEL
Benign
0.17
Sift
Benign
0.18
T;T;.
Sift4G
Benign
0.52
T;T;T
Polyphen
0.0070
B;.;.
Vest4
0.15
MVP
0.76
MPC
0.44
ClinPred
0.073
T
GERP RS
2.5
Varity_R
0.071
gMVP
0.30
Mutation Taster
=94/6
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs376604413; hg19: chr17-7350937; API