rs755416498

Positions:

chr20-63349957-C-T

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 0P and 10B. BP4BP6BS1BS2

The NM_000744.7(CHRNA4):c.1454G>A(p.Arg485Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000466 in 1,567,018 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 34)

Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 7.39

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 -10 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.33719644).

BP6

Variant 20-63349957-C-T is Benign according to our data. Variant chr20-63349957-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 197690.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.0000722 (11/152300) while in subpopulation AMR AF= 0.000588 (9/15302). AF 95% confidence interval is 0.000306. There are 0 homozygotes in gnomad4. There are 7 alleles in male gnomad4 subpopulation. Median coverage is 34. This position pass quality control queck.

BS2

High AC in GnomAd4 at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNA4	NM_000744.7 linkuse as main transcript	c.1454G>A	p.Arg485Gln	missense_variant	5/6	ENST00000370263.9	NP_000735.1	P43681-1B4DK78Q59FV0
CHRNA4	NM_001256573.2 linkuse as main transcript	c.926G>A	p.Arg309Gln	missense_variant	5/6		NP_001243502.1	P43681Q4VAQ3B4DK78Q59FV0
CHRNA4	NR_046317.2 linkuse as main transcript	n.1663G>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.1454G>A	p.Arg485Gln	missense_variant	5/6	1	NM_000744.7	ENSP00000359285.4		P43681-1

Frequencies

GnomAD3 genomes

AF:

0.0000723

AC:

AN:

152182

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000589

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000224

AC:

AN:

182690

Hom.:

AF XY:

0.000171

AC XY:

AN XY:

99292

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00140

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000144

Gnomad SAS exome

AF:

0.0000406

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000438

AC:

AN:

1414718

Hom.:

Cov.:

AF XY:

0.0000372

AC XY:

AN XY:

698602

show subpopulations

Gnomad4 AFR exome

AF:

0.0000307

Gnomad4 AMR exome

AF:

0.00125

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000106

Gnomad4 SAS exome

AF:

0.0000246

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000552

Gnomad4 OTH exome

AF:

0.0000172

GnomAD4 genome

AF:

0.0000722

AC:

AN:

152300

Hom.:

Cov.:

AF XY:

0.0000940

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000588

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000194

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000982

ExAC

AF:

0.0000760

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:1Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jan 27, 2015	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 16, 2020	- -

Autosomal dominant nocturnal frontal lobe epilepsy

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 01, 2024

- -

Inborn genetic diseases

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 03, 2024

This alteration is classified as 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Uncertain

0.0

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.34

T;.

Eigen

Uncertain

0.61

Eigen_PC

Uncertain

0.58

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.95

D;D

M_CAP

Pathogenic

0.42

MetaRNN

Benign

0.34

T;T

MetaSVM

Benign

-0.30

MutationAssessor

Uncertain

2.2

M;.

PrimateAI

Uncertain

0.52

PROVEAN

Benign

-0.55

N;.

REVEL

Uncertain

0.48

Sift

Benign

0.11

T;.

Sift4G

Benign

0.24

T;T

Polyphen

1.0

D;.

Vest4

0.78

MutPred

0.50

Loss of catalytic residue at R485 (P = 0.0311);.;

MVP

0.86

MPC

1.3

ClinPred

0.23

GERP RS

4.9

Varity_R

0.15

gMVP

0.48

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