rs201004255

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 4P and 5B. PP3_StrongBP6BS2

The NM_000748.3(CHRNB2):​c.968A>G​(p.His323Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,614,000 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

CHRNB2
NM_000748.3 missense

Scores

9
8
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:1

Conservation

PhyloP100: 9.27

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 -1 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.94
BP6
Variant 1-154571791-A-G is Benign according to our data. Variant chr1-154571791-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 573599.
BS2
High AC in GnomAdExome4 at 19 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB2NM_000748.3 linkc.968A>G p.His323Arg missense_variant Exon 5 of 6 ENST00000368476.4 NP_000739.1 P17787Q5SXY3
CHRNB2XM_017000180.3 linkc.458A>G p.His153Arg missense_variant Exon 2 of 3 XP_016855669.1
CHRNB2XR_001736952.3 linkn.1235A>G 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.968A>G p.His323Arg missense_variant Exon 5 of 6 1 NM_000748.3 ENSP00000357461.3 P17787
CHRNB2ENST00000637900.1 linkc.974A>G p.His325Arg missense_variant Exon 5 of 6 5 ENSP00000490474.1 A0A1B0GVD7
CHRNB2ENST00000636034.1 linkn.968A>G non_coding_transcript_exon_variant Exon 5 of 9 5 ENSP00000489703.1 A0A1B0GTH5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152224
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:
250722
AF XY:
0.0000295
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:
0.0000618
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461776
Hom.:
0
Cov.:
33
AF XY:
0.0000151
AC XY:
11
AN XY:
727188
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:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53316
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000162
AC:
18
AN:
1112006
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
Heterozygous variant carriers
0
2
3
5
6
8
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:
152224
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
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:
0.0000868
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Autosomal dominant nocturnal frontal lobe epilepsy Uncertain:1
Jan 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 323 of the CHRNB2 protein (p.His323Arg). This variant is present in population databases (rs201004255, gnomAD 0.006%). This missense change has been observed in individual(s) with clinical features of CHRNB2-related conditions (Invitae). ClinVar contains an entry for this variant (Variation ID: 573599). 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 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
May 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CHRNB2: PP2, PP3 -

Inborn genetic diseases Benign:1
Jun 05, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.90
BayesDel_addAF
Uncertain
0.072
D
BayesDel_noAF
Uncertain
0.050
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.84
D;.
Eigen
Pathogenic
0.75
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.80
T;T
M_CAP
Uncertain
0.13
D
MetaRNN
Pathogenic
0.94
D;D
MetaSVM
Uncertain
0.67
D
MutationAssessor
Pathogenic
3.5
M;.
PhyloP100
9.3
PrimateAI
Pathogenic
0.83
D
PROVEAN
Pathogenic
-6.2
D;.
REVEL
Pathogenic
0.83
Sift
Uncertain
0.015
D;.
Sift4G
Uncertain
0.017
D;.
Polyphen
1.0
D;.
Vest4
0.85
MutPred
0.83
Gain of relative solvent accessibility (P = 0.1259);.;
MVP
0.93
MPC
2.5
ClinPred
0.94
D
GERP RS
4.0
Varity_R
0.94
gMVP
0.97
Mutation Taster
=33/67
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: rs201004255; hg19: chr1-154544267; API