1-154571514-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PP3_ModerateBS2

The NM_000748.3(CHRNB2):​c.691C>T​(p.Arg231Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,808 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. R231R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

CHRNB2
NM_000748.3 missense

Scores

9
8
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.37

Publications

0 publications found
Variant links:
Genes affected
CHRNB2 (HGNC:1962): (cholinergic receptor nicotinic beta 2 subunit) Neuronal acetylcholine receptors are homo- or heteropentameric complexes composed of homologous alpha and beta subunits. They belong to a superfamily of ligand-gated ion channels which allow the flow of sodium and potassium across the plasma membrane in response to ligands such as acetylcholine and nicotine. This gene encodes one of several beta subunits. Mutations in this gene are associated with autosomal dominant nocturnal frontal lobe epilepsy. [provided by RefSeq, Jul 2008]
CHRNB2 Gene-Disease associations (from GenCC):
  • familial sleep-related hypermotor epilepsy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • autosomal dominant nocturnal frontal lobe epilepsy 3
    Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • autosomal dominant nocturnal frontal lobe epilepsy
    Inheritance: AD 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.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.864
BS2
High AC in GnomAdExome4 at 10 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB2NM_000748.3 linkc.691C>T p.Arg231Cys missense_variant Exon 5 of 6 ENST00000368476.4 NP_000739.1 P17787Q5SXY3
CHRNB2XM_017000180.3 linkc.181C>T p.Arg61Cys missense_variant Exon 2 of 3 XP_016855669.1
CHRNB2XR_001736952.3 linkn.958C>T non_coding_transcript_exon_variant Exon 5 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNB2ENST00000368476.4 linkc.691C>T p.Arg231Cys missense_variant Exon 5 of 6 1 NM_000748.3 ENSP00000357461.3 P17787
CHRNB2ENST00000637900.1 linkc.697C>T p.Arg233Cys missense_variant Exon 5 of 6 5 ENSP00000490474.1 A0A1B0GVD7
CHRNB2ENST00000636034.1 linkn.691C>T non_coding_transcript_exon_variant Exon 5 of 9 5 ENSP00000489703.1 A0A1B0GTH5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.0000279
AC:
7
AN:
251136
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000202
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461680
Hom.:
0
Cov.:
33
AF XY:
0.00000825
AC XY:
6
AN XY:
727160
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000134
AC:
6
AN:
44724
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:
0.00
AC:
0
AN:
53218
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1112004
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74308
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41424
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68010
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal dominant nocturnal frontal lobe epilepsy Uncertain:1
Oct 06, 2024
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 cysteine, which is neutral and slightly polar, at codon 231 of the CHRNB2 protein (p.Arg231Cys). This variant is present in population databases (rs752986234, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with CHRNB2-related conditions. ClinVar contains an entry for this variant (Variation ID: 410308). 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) indicates that this missense variant is not expected to disrupt CHRNB2 protein function with a negative predictive value of 80%. 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
Oct 30, 2018
Athena Diagnostics
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
Uncertain
0.43
BayesDel_addAF
Benign
-0.081
T
BayesDel_noAF
Uncertain
-0.070
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.95
D;.
Eigen
Uncertain
0.48
Eigen_PC
Uncertain
0.38
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.86
D;D
MetaSVM
Uncertain
0.32
D
MutationAssessor
Pathogenic
3.0
M;.
PhyloP100
1.4
PrimateAI
Uncertain
0.74
T
PROVEAN
Pathogenic
-6.4
D;.
REVEL
Pathogenic
0.77
Sift
Pathogenic
0.0
D;.
Sift4G
Pathogenic
0.0
D;.
Polyphen
1.0
D;.
Vest4
0.62
MutPred
0.74
Gain of ubiquitination at K233 (P = 0.0726);.;
MVP
0.89
MPC
2.6
ClinPred
0.98
D
GERP RS
3.2
Varity_R
0.82
gMVP
0.93
Mutation Taster
=42/58
disease causing

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: rs752986234; hg19: chr1-154543990; COSMIC: COSV108201129; COSMIC: COSV108201129; API