rs796052329

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PM4_SupportingBP6BS2

The ENST00000368476.4(CHRNB2):​c.352_354delCAA​(p.Val118del) variant causes a conservative inframe deletion change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000487 in 1,600,848 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00029 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

CHRNB2
ENST00000368476.4 conservative_inframe_deletion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 9.32

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 -4 ACMG points.

PM4
Nonframeshift variant in NON repetitive region in ENST00000368476.4. Strenght limited to Supporting due to length of the change: 1aa.
BP6
Variant 1-154570360-TACA-T is Benign according to our data. Variant chr1-154570360-TACA-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 205077.
BS2
High AC in GnomAd4 at 44 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNB2NM_000748.3 linkc.363_365delCAA p.Asn122del disruptive_inframe_deletion, splice_region_variant Exon 4 of 6 ENST00000368476.4 NP_000739.1
CHRNB2XM_017000180.3 linkc.-12_-10delCAA splice_region_variant Exon 1 of 3 XP_016855669.1
CHRNB2XR_001736952.3 linkn.630_632delCAA splice_region_variant, non_coding_transcript_exon_variant Exon 4 of 7
CHRNB2XM_017000180.3 linkc.-12_-10delCAA 5_prime_UTR_variant Exon 1 of 3 XP_016855669.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNB2ENST00000368476.4 linkc.352_354delCAA p.Val118del conservative_inframe_deletion Exon 4 of 6 1 NM_000748.3 ENSP00000357461.3
CHRNB2ENST00000637900.1 linkc.358_360delCAA p.Val120del conservative_inframe_deletion Exon 4 of 6 5 ENSP00000490474.1
CHRNB2ENST00000636034.1 linkn.352_354delCAA non_coding_transcript_exon_variant Exon 4 of 9 5 ENSP00000489703.1
CHRNB2ENST00000636695.1 linkn.*86_*88delACA downstream_gene_variant 5

Frequencies

GnomAD3 genomes
AF:
0.000290
AC:
44
AN:
151980
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00242
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:
0.00
Gnomad OTH
AF:
0.00287
GnomAD2 exomes
AF:
0.0000532
AC:
13
AN:
244296
AF XY:
0.0000304
show subpopulations
Gnomad AFR exome
AF:
0.0000653
Gnomad AMR exome
AF:
0.000235
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:
0.000664
GnomAD4 exome
AF:
0.0000235
AC:
34
AN:
1448750
Hom.:
0
AF XY:
0.0000125
AC XY:
9
AN XY:
720856
show subpopulations
African (AFR)
AF:
0.0000301
AC:
1
AN:
33226
American (AMR)
AF:
0.000519
AC:
23
AN:
44346
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25878
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39646
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85174
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53190
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1101618
Other (OTH)
AF:
0.000167
AC:
10
AN:
59920
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
Heterozygous variant carriers
0
3
5
8
10
13
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:
0.000289
AC:
44
AN:
152098
Hom.:
0
Cov.:
31
AF XY:
0.000269
AC XY:
20
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41492
American (AMR)
AF:
0.00242
AC:
37
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5162
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4806
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67968
Other (OTH)
AF:
0.00284
AC:
6
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.000130
Hom.:
0
Bravo
AF:
0.000646

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
May 25, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In-frame deletion of 1 amino acid in a non-repeat region; In silico analysis supports a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Dec 29, 2017
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal dominant nocturnal frontal lobe epilepsy 3 Uncertain:1
Jan 21, 2021
New York Genome Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Jan 06, 2017
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.363_365delCAA variant (also known as p.N122del) is located in coding exon 4 of the CHRNB2 gene. This variant results from an in-frame CAA deletion at nucleotide positions 363 to 365. This results in the in-frame deletion of an asparagine at codon 122. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by PROVEAN in silico analysis (Choi Y et al., PLoS ONE 2012; 7(10):e46688). Since supporting evidence is limited at this time, the clinical significance of this variant remains unclear. -

Autosomal dominant nocturnal frontal lobe epilepsy Benign:1
Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
9.3
Mutation Taster
=14/86
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs796052329; hg19: chr1-154542836; API