rs541282922

Positions:

Variant summary

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

The NM_000742.4(CHRNA2):c.347G>T(p.Ser116Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000127 in 1,610,348 control chromosomes in the GnomAD database, including 5 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00014 ( 5 hom. )

Consequence

CHRNA2
NM_000742.4 missense

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: -0.376

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]

CHRNA2 links:

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 (MetaRNN=0.050329536).

BP6

Variant 8-27467331-C-A is Benign according to our data. Variant chr8-27467331-C-A is described in ClinVar as [Likely_benign]. Clinvar id is 204945.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS2

High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNA2	NM_000742.4 linkuse as main transcript	c.347G>T	p.Ser116Ile	missense_variant	5/7	ENST00000407991.3	NP_000733.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNA2	ENST00000407991.3 linkuse as main transcript	c.347G>T	p.Ser116Ile	missense_variant	5/7	5	NM_000742.4	ENSP00000385026	P2	Q15822-1

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152226

Hom.:

Cov.:

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:

0.00145

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000270

AC:

AN:

251448

Hom.:

AF XY:

0.000375

AC XY:

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000867

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00212

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000135

AC:

197

AN:

1458004

Hom.:

Cov.:

AF XY:

0.000208

AC XY:

151

AN XY:

725528

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000895

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00212

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.02e-7

Gnomad4 OTH exome

AF:

0.0000830

GnomAD4 genome

AF:

0.0000525

AC:

AN:

152344

Hom.:

Cov.:

AF XY:

0.0000806

AC XY:

AN XY:

74482

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00145

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000136

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.000272

AC:

Asia WGS

AF:

0.000577

AC:

AN:

3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:3

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 submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 02, 2020

- -

not provided

Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

Dec 21, 2020

- -

CHRNA2-related disorder

Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 01, 2019

This 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

AlphaMissense

Benign

0.13

BayesDel_addAF

Benign

-0.46

BayesDel_noAF

Benign

-0.44

CADD

Benign

6.5

DANN

Benign

0.31

DEOGEN2

Benign

0.36

T;.;.

Eigen

Benign

-1.5

Eigen_PC

Benign

-1.5

FATHMM_MKL

Benign

0.083

LIST_S2

Benign

0.70

T;T;T

M_CAP

Benign

0.024

MetaRNN

Benign

0.050

T;T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

-0.17

N;.;.

MutationTaster

Benign

1.0

N;N;N

PrimateAI

Benign

0.43

PROVEAN

Benign

-1.9

N;.;N

REVEL

Benign

0.094

Sift

Benign

0.34

T;.;T

Sift4G

Benign

0.54

T;T;T

Polyphen

0.0040

B;.;.

Vest4

0.45

MutPred

0.33

Gain of methylation at K119 (P = 0.0786);.;.;

MVP

0.53

MPC

0.52

ClinPred

0.025

GERP RS

-5.6

Varity_R

0.11

gMVP

0.43

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over