8-27463477-C-T

Variant summary

Our verdict is Benign. Variant got -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_000742.4(CHRNA2):​c.966G>A​(p.Ser322=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000793 in 1,614,132 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00027 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000060 ( 0 hom. )

Consequence

CHRNA2
NM_000742.4 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: -1.36
Variant links:
Genes affected
CHRNA2 (HGNC:1956): (cholinergic receptor nicotinic alpha 2 subunit) Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels formed by a pentameric arrangement of alpha and beta subunits to create distinct muscle and neuronal receptors. Neuronal receptors are found throughout the peripheral and central nervous system where they are involved in fast synaptic transmission. This gene encodes an alpha subunit that is widely expressed in the brain. The proposed structure for nAChR subunits is a conserved N-terminal extracellular domain followed by three conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region. Mutations in this gene cause autosomal dominant nocturnal frontal lobe epilepsy type 4. Single nucleotide polymorphisms (SNPs) in this gene have been associated with nicotine dependence. [provided by RefSeq, Nov 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -16 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.55).
BP6
Variant 8-27463477-C-T is Benign according to our data. Variant chr8-27463477-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 384605.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAd4 at 41 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CHRNA2NM_000742.4 linkuse as main transcriptc.966G>A p.Ser322= synonymous_variant 6/7 ENST00000407991.3 NP_000733.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CHRNA2ENST00000407991.3 linkuse as main transcriptc.966G>A p.Ser322= synonymous_variant 6/75 NM_000742.4 ENSP00000385026 P2Q15822-1

Frequencies

GnomAD3 genomes
AF:
0.000269
AC:
41
AN:
152134
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000942
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:
0.000478
GnomAD3 exomes
AF:
0.0000597
AC:
15
AN:
251446
Hom.:
0
AF XY:
0.0000294
AC XY:
4
AN XY:
135912
show subpopulations
Gnomad AFR exome
AF:
0.000861
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000595
AC:
87
AN:
1461880
Hom.:
0
Cov.:
33
AF XY:
0.0000509
AC XY:
37
AN XY:
727238
show subpopulations
Gnomad4 AFR exome
AF:
0.000597
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000531
Gnomad4 OTH exome
AF:
0.000116
GnomAD4 genome
AF:
0.000269
AC:
41
AN:
152252
Hom.:
0
Cov.:
33
AF XY:
0.000242
AC XY:
18
AN XY:
74440
show subpopulations
Gnomad4 AFR
AF:
0.000939
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.000473
Alfa
AF:
0.0000965
Hom.:
0
Bravo
AF:
0.000242

ClinVar

Significance: Likely benign
Submissions summary: Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal dominant nocturnal frontal lobe epilepsy Benign:1
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 14, 2024- -
Inborn genetic diseases Benign:1
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsMay 09, 2016This 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. -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxMay 28, 2021- -
CHRNA2-related disorder Benign:1
Likely benign, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesMar 20, 2019This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.55
CADD
Benign
10
DANN
Benign
0.91

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs140118184; hg19: chr8-27320994; API