chr20-63349700-C-T

Position:

chr20-63349700-C-T

Variant summary

Our verdict is Benign. Variant got -18 ACMG points: 0P and 18B. BP4_ModerateBP6_Very_StrongBS1BS2

The NM_000744.7(CHRNA4):c.1711G>A(p.Val571Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000118 in 1,612,874 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 0.00028 ( 0 hom., cov: 34)

Exomes 𝑓: 0.00010 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:2O:1

Conservation

PhyloP100: 2.67

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 -18 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.1426808).

BP6

Variant 20-63349700-C-T is Benign according to our data. Variant chr20-63349700-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 98323.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-63349700-C-T is described in Lovd as [Likely_benign].

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000276 (42/152368) while in subpopulation AMR AF= 0.000914 (14/15312). AF 95% confidence interval is 0.000552. There are 0 homozygotes in gnomad4. There are 17 alleles in male gnomad4 subpopulation. Median coverage is 34. This position pass quality control queck.

BS2

High AC in GnomAd4 at 42 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
CHRNA4	NM_000744.7 linkuse as main transcript	c.1711G>A	p.Val571Ile	missense_variant	5/6	ENST00000370263.9	NP_000735.1
CHRNA4	NM_001256573.2 linkuse as main transcript	c.1183G>A	p.Val395Ile	missense_variant	5/6		NP_001243502.1
CHRNA4	NR_046317.2 linkuse as main transcript	n.1920G>A		non_coding_transcript_exon_variant	5/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNA4	ENST00000370263.9 linkuse as main transcript	c.1711G>A	p.Val571Ile	missense_variant	5/6	1	NM_000744.7	ENSP00000359285	P1	P43681-1

Frequencies

GnomAD3 genomes

AF:

0.000276

AC:

AN:

152250

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000458

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000916

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:

0.000132

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000222

AC:

AN:

248188

Hom.:

AF XY:

0.000178

AC XY:

AN XY:

134940

show subpopulations

Gnomad AFR exome

AF:

0.000376

Gnomad AMR exome

AF:

0.000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000547

Gnomad SAS exome

AF:

0.0000654

Gnomad FIN exome

AF:

0.0000463

Gnomad NFE exome

AF:

0.000306

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.000101

AC:

148

AN:

1460506

Hom.:

Cov.:

AF XY:

0.0000867

AC XY:

AN XY:

726582

show subpopulations

Gnomad4 AFR exome

AF:

0.000418

Gnomad4 AMR exome

AF:

0.000268

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000580

Gnomad4 FIN exome

AF:

0.0000191

Gnomad4 NFE exome

AF:

0.0000998

Gnomad4 OTH exome

AF:

0.0000663

GnomAD4 genome

AF:

0.000276

AC:

AN:

152368

Hom.:

Cov.:

AF XY:

0.000228

AC XY:

AN XY:

74498

show subpopulations

Gnomad4 AFR

AF:

0.000457

Gnomad4 AMR

AF:

0.000914

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000132

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000288

Hom.:

Bravo

AF:

0.000295

ESP6500AA

AF:

0.000454

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.000289

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000356

ClinVar

Significance: Likely benign

Submissions summary: Benign:2Other:1

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

Jan 04, 2024

- -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Jul 23, 2019

This variant is associated with the following publications: (PMID: 22873564, 21683344) -

Tobacco use disorder

Other:1

not provided, no classification provided

literature only

Psychiatry Genetics Yale University

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.10

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.21

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.27

T;.

Eigen

Benign

0.18

Eigen_PC

Benign

0.11

FATHMM_MKL

Uncertain

0.93

LIST_S2

Uncertain

0.91

D;D

M_CAP

Uncertain

0.13

MetaRNN

Benign

0.14

T;T

MetaSVM

Uncertain

0.20

MutationAssessor

Uncertain

2.3

M;.

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.51

PROVEAN

Benign

-0.80

N;.

REVEL

Uncertain

0.42

Sift

Benign

0.067

T;.

Sift4G

Benign

0.15

T;T

Polyphen

1.0

D;.

Vest4

0.14

MVP

0.82

MPC

0.38

ClinPred

0.032

GERP RS

2.8

Varity_R

0.061

gMVP

0.68

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