NM_000748.3:c.1378C>T

Variant summary

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

The NM_000748.3(CHRNB2):​c.1378C>T​(p.Arg460Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,996 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R460H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

CHRNB2
NM_000748.3 missense

Scores

17
1
1

Clinical Significance

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

Conservation

PhyloP100: 2.12

Publications

5 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, 0.981
BP6
Variant 1-154575801-C-T is Benign according to our data. Variant chr1-154575801-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1356911.
BS2
High AC in GnomAdExome4 at 24 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB2NM_000748.3 linkc.1378C>T p.Arg460Cys missense_variant Exon 6 of 6 ENST00000368476.4 NP_000739.1 P17787Q5SXY3
CHRNB2XM_017000180.3 linkc.868C>T p.Arg290Cys missense_variant Exon 3 of 3 XP_016855669.1
CHRNB2XR_001736952.3 linkn.1645C>T non_coding_transcript_exon_variant Exon 6 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNB2ENST00000368476.4 linkc.1378C>T p.Arg460Cys missense_variant Exon 6 of 6 1 NM_000748.3 ENSP00000357461.3 P17787
CHRNB2ENST00000637900.1 linkc.1384C>T p.Arg462Cys missense_variant Exon 6 of 6 5 ENSP00000490474.1 A0A1B0GVD7
CHRNB2ENST00000636034.1 linkn.1378C>T non_coding_transcript_exon_variant Exon 6 of 9 5 ENSP00000489703.1 A0A1B0GTH5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152110
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:
0.0000199
AC:
5
AN:
251478
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:
0.000185
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1461886
Hom.:
0
Cov.:
31
AF XY:
0.0000248
AC XY:
18
AN XY:
727244
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:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.000150
AC:
8
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
2
4
5
7
9
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:
152110
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74306
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15256
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2082
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00000872
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

Autosomal dominant nocturnal frontal lobe epilepsy Uncertain:1
Jul 09, 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 expected to disrupt CHRNB2 protein function. ClinVar contains an entry for this variant (Variation ID: 1356911). This variant has not been reported in the literature in individuals affected with CHRNB2-related conditions. This variant is present in population databases (rs202079239, gnomAD 0.02%). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 460 of the CHRNB2 protein (p.Arg460Cys). -

Inborn genetic diseases Benign:1
Dec 06, 2022
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
0.94
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.42
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.96
D;.
Eigen
Pathogenic
0.92
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Pathogenic
1.0
D;D
M_CAP
Pathogenic
0.31
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.8
H;.
PhyloP100
2.1
PrimateAI
Pathogenic
0.83
D
PROVEAN
Pathogenic
-7.4
D;.
REVEL
Pathogenic
0.88
Sift
Pathogenic
0.0
D;.
Sift4G
Pathogenic
0.0
D;.
Polyphen
1.0
D;.
Vest4
0.86
MutPred
0.91
Gain of catalytic residue at L461 (P = 0.0286);.;
MVP
0.97
MPC
0.75
ClinPred
1.0
D
GERP RS
5.2
Varity_R
0.98
gMVP
0.94
Mutation Taster
=17/83
disease causing

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: rs202079239; hg19: chr1-154548277; API