1-154569474-C-T

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_000748.3(CHRNB2):​c.77C>T​(p.Thr26Met) variant causes a missense change. The variant allele was found at a frequency of 0.000813 in 1,613,812 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. T26T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00053 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00084 ( 2 hom. )

Consequence

CHRNB2
NM_000748.3 missense

Scores

9
10

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 4.14

Publications

9 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: Benign. The variant received -16 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.055544734).
BP6
Variant 1-154569474-C-T is Benign according to our data. Variant chr1-154569474-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 205061.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAd4 at 80 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB2NM_000748.3 linkc.77C>T p.Thr26Met missense_variant Exon 2 of 6 ENST00000368476.4 NP_000739.1 P17787Q5SXY3
CHRNB2XR_001736952.3 linkn.344C>T non_coding_transcript_exon_variant Exon 2 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNB2ENST00000368476.4 linkc.77C>T p.Thr26Met missense_variant Exon 2 of 6 1 NM_000748.3 ENSP00000357461.3 P17787
CHRNB2ENST00000637900.1 linkc.77C>T p.Thr26Met missense_variant Exon 2 of 6 5 ENSP00000490474.1 A0A1B0GVD7
CHRNB2ENST00000636034.1 linkn.77C>T non_coding_transcript_exon_variant Exon 2 of 9 5 ENSP00000489703.1 A0A1B0GTH5
CHRNB2ENST00000636695.1 linkn.-54C>T upstream_gene_variant 5

Frequencies

GnomAD3 genomes
AF:
0.000526
AC:
80
AN:
152026
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000622
Gnomad FIN
AF:
0.0000943
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000985
Gnomad OTH
AF:
0.000479
GnomAD2 exomes
AF:
0.000677
AC:
170
AN:
251214
AF XY:
0.000766
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000318
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.000139
Gnomad NFE exome
AF:
0.00115
Gnomad OTH exome
AF:
0.000652
GnomAD4 exome
AF:
0.000843
AC:
1232
AN:
1461668
Hom.:
2
Cov.:
34
AF XY:
0.000825
AC XY:
600
AN XY:
727130
show subpopulations
African (AFR)
AF:
0.000149
AC:
5
AN:
33478
American (AMR)
AF:
0.000380
AC:
17
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.000696
AC:
60
AN:
86226
European-Finnish (FIN)
AF:
0.000243
AC:
13
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5672
European-Non Finnish (NFE)
AF:
0.000986
AC:
1096
AN:
1111950
Other (OTH)
AF:
0.000662
AC:
40
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
71
142
213
284
355
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
38
76
114
152
190
<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:
0.000526
AC:
80
AN:
152144
Hom.:
0
Cov.:
31
AF XY:
0.000565
AC XY:
42
AN XY:
74388
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41484
American (AMR)
AF:
0.000131
AC:
2
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.000622
AC:
3
AN:
4822
European-Finnish (FIN)
AF:
0.0000943
AC:
1
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000986
AC:
67
AN:
67982
Other (OTH)
AF:
0.000474
AC:
1
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
4
8
12
16
20
<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:
0.000763
Hom.:
1
Bravo
AF:
0.000567
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000778
AC:
3
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000930
AC:
8
ExAC
AF:
0.000815
AC:
99
EpiCase
AF:
0.000763
EpiControl
AF:
0.00107

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:2
Nov 06, 2019
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CHRNB2: PP2, BP4, BS1 -

not specified Benign:1
Jan 30, 2020
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal dominant nocturnal frontal lobe epilepsy Benign:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
May 08, 2019
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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
Benign
0.12
BayesDel_addAF
Benign
-0.27
T
BayesDel_noAF
Benign
-0.21
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.31
T;.
Eigen
Uncertain
0.44
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Uncertain
0.89
D;D
M_CAP
Benign
0.080
D
MetaRNN
Benign
0.056
T;T
MetaSVM
Uncertain
-0.23
T
MutationAssessor
Benign
1.2
L;.
PhyloP100
4.1
PrimateAI
Uncertain
0.48
T
PROVEAN
Benign
-1.3
N;.
REVEL
Uncertain
0.31
Sift
Benign
0.075
T;.
Sift4G
Uncertain
0.011
D;.
Polyphen
1.0
D;.
Vest4
0.25
MVP
0.75
MPC
1.2
ClinPred
0.074
T
GERP RS
4.5
Varity_R
0.072
gMVP
0.50
Mutation Taster
=62/38
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: rs71651692; hg19: chr1-154541950; COSMIC: COSV63809532; COSMIC: COSV63809532; API