rs200259564

Positions:

chr20-63350919-G-A

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_000744.7(CHRNA4):c.492C>T(p.Asp164=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000208 in 1,613,960 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 (★★).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 31)

Exomes 𝑓: 0.00022 ( 2 hom. )

Consequence

CHRNA4
NM_000744.7 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:4O:1

Conservation

PhyloP100: -0.703

Variant links:

Genes affected

CHRNA4 (HGNC:1958): (cholinergic receptor nicotinic alpha 4 subunit) This gene encodes a nicotinic acetylcholine receptor, which belongs to a superfamily of ligand-gated ion channels that play a role in fast signal transmission at synapses. These pentameric receptors can bind acetylcholine, which causes an extensive change in conformation that leads to the opening of an ion-conducting channel across the plasma membrane. This protein is an integral membrane receptor subunit that can interact with either nAChR beta-2 or nAChR beta-4 to form a functional receptor. Mutations in this gene cause nocturnal frontal lobe epilepsy type 1. Polymorphisms in this gene that provide protection against nicotine addiction have been described. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2012]

CHRNA4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -21 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.6).

BP6

Variant 20-63350919-G-A is Benign according to our data. Variant chr20-63350919-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 416915.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP7

Synonymous conserved (PhyloP=-0.703 with no splicing effect.

BS1

Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000118 (18/152216) while in subpopulation SAS AF= 0.00228 (11/4816). AF 95% confidence interval is 0.00128. There are 0 homozygotes in gnomad4. There are 11 alleles in male gnomad4 subpopulation. Median coverage is 31. This position pass quality control queck.

BS2

High AC in GnomAd4 at 18 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
CHRNA4	NM_000744.7 linkuse as main transcript	c.492C>T	p.Asp164=	synonymous_variant	5/6	ENST00000370263.9
CHRNA4	NM_001256573.2 linkuse as main transcript	c.-37C>T		5_prime_UTR_variant	5/6
CHRNA4	NR_046317.2 linkuse as main transcript	n.701C>T		non_coding_transcript_exon_variant	5/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHRNA4	ENST00000370263.9 linkuse as main transcript	c.492C>T	p.Asp164=	synonymous_variant	5/6	1	NM_000744.7	P1	P43681-1

Frequencies

GnomAD3 genomes

AF:

0.000118

AC:

AN:

152098

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00228

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000462

AC:

116

AN:

251160

Hom.:

AF XY:

0.000508

AC XY:

AN XY:

135882

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000381

Gnomad SAS exome

AF:

0.00284

Gnomad FIN exome

AF:

0.0000924

Gnomad NFE exome

AF:

0.000150

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000218

AC:

318

AN:

1461744

Hom.:

Cov.:

AF XY:

0.000254

AC XY:

185

AN XY:

727148

show subpopulations

Gnomad4 AFR exome

AF:

0.000119

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000756

Gnomad4 SAS exome

AF:

0.00177

Gnomad4 FIN exome

AF:

0.0000751

Gnomad4 NFE exome

AF:

0.000128

Gnomad4 OTH exome

AF:

0.000166

GnomAD4 genome

AF:

0.000118

AC:

AN:

152216

Hom.:

Cov.:

AF XY:

0.000148

AC XY:

AN XY:

74414

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00228

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000131

Hom.:

Bravo

AF:

0.0000756

EpiCase

AF:

0.000164

EpiControl

AF:

0.000296

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:4Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:1Other:1

Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 03, 2015	- -
not provided, no classification provided	in vitro	Seelig Lab, University of Washington	-	- -

Autosomal dominant nocturnal frontal lobe epilepsy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 17, 2024

- -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 31, 2016

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. -

Autosomal dominant nocturnal frontal lobe epilepsy 1;C1861063:Tobacco addiction, susceptibility to

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 04, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.60

CADD

Benign

6.2

DANN

Benign

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

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