rs747883053

Positions:

chr20-63349891-G-A

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000744.7(CHRNA4):c.1520C>T(p.Ala507Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000113 in 1,593,014 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 0.331

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:

CHRNA4 (HGNC:):

CHRNA4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.04828626).

BP6

Variant 20-63349891-G-A is Benign according to our data. Variant chr20-63349891-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 205033.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.0000118 (17/1440838) while in subpopulation AMR AF= 0.000371 (16/43178). AF 95% confidence interval is 0.000232. There are 0 homozygotes in gnomad4_exome. There are 6 alleles in male gnomad4_exome subpopulation. Median coverage is 83. This position pass quality control queck.

BS2

High AC in GnomAdExome4 at 17 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNA4	NM_000744.7 linkuse as main transcript	c.1520C>T	p.Ala507Val	missense_variant	5/6	ENST00000370263.9	NP_000735.1	P43681-1B4DK78Q59FV0
CHRNA4	NM_001256573.2 linkuse as main transcript	c.992C>T	p.Ala331Val	missense_variant	5/6		NP_001243502.1	P43681Q4VAQ3B4DK78Q59FV0
CHRNA4	NR_046317.2 linkuse as main transcript	n.1729C>T		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.1520C>T	p.Ala507Val	missense_variant	5/6	1	NM_000744.7	ENSP00000359285.4		P43681-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152176

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.00

GnomAD3 exomes

AF:

0.0000790

AC:

AN:

227842

Hom.:

AF XY:

0.0000564

AC XY:

AN XY:

124202

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000490

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:

0.0000197

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000118

AC:

AN:

1440838

Hom.:

Cov.:

AF XY:

0.00000841

AC XY:

AN XY:

713782

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000371

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.09e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152176

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74336

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000868

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.0000832

AC:

ClinVar

Significance: 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

Jan 06, 2024

- -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 31, 2019

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. -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Apr 21, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.084

BayesDel_addAF

Benign

-0.35

BayesDel_noAF

Benign

-0.41

CADD

Benign

DANN

Benign

0.95

DEOGEN2

Benign

0.27

T;.

Eigen

Benign

-1.4

Eigen_PC

Benign

-1.5

FATHMM_MKL

Benign

0.13

LIST_S2

Benign

0.49

T;T

M_CAP

Uncertain

0.10

MetaRNN

Benign

0.048

T;T

MetaSVM

Benign

-0.93

MutationAssessor

Benign

2.0

M;.

PrimateAI

Benign

0.41

PROVEAN

Benign

0.070

N;.

REVEL

Benign

0.15

Sift

Benign

0.17

T;.

Sift4G

Benign

0.56

T;T

Polyphen

0.039

B;.

Vest4

0.12

MutPred

0.34

Loss of relative solvent accessibility (P = 0.0186);.;

MVP

0.49

MPC

0.42

ClinPred

0.040

GERP RS

-1.7

Varity_R

0.026

gMVP

0.25

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