rs377114983

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 4P and 4B. PP3_StrongBS2

The NM_000744.7(CHRNA4):c.362C>T(p.Pro121Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,611,800 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 30)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.76

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 Uncertain_significance. Variant got 0 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.976

BS2

High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
CHRNA4	NM_000744.7 linkuse as main transcript	c.362C>T	p.Pro121Leu	missense_variant	4/6	ENST00000370263.9	NP_000735.1
CHRNA4	NM_001256573.2 linkuse as main transcript	c.-185C>T		5_prime_UTR_variant	4/6		NP_001243502.1
CHRNA4	NR_046317.2 linkuse as main transcript	n.571C>T		non_coding_transcript_exon_variant	4/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNA4	ENST00000370263.9 linkuse as main transcript	c.362C>T	p.Pro121Leu	missense_variant	4/6	1	NM_000744.7	ENSP00000359285	P1	P43681-1

Frequencies

GnomAD3 genomes

AF:

0.0000198

AC:

AN:

151290

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000730

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1460510

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

726556

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

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:

0.00000360

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000198

AC:

AN:

151290

Hom.:

Cov.:

AF XY:

0.0000271

AC XY:

AN XY:

73846

show subpopulations

Gnomad4 AFR

AF:

0.0000730

Gnomad4 AMR

AF:

0.00

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

Bravo

AF:

0.0000302

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

CHRNA4-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 21, 2023

The CHRNA4 c.362C>T variant is predicted to result in the amino acid substitution p.Pro121Leu. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0040% of alleles in individuals of European (Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/20-61987348-G-A). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Autosomal dominant nocturnal frontal lobe epilepsy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 26, 2022

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 121 of the CHRNA4 protein (p.Pro121Leu). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 581212). This variant has not been reported in the literature in individuals affected with CHRNA4-related conditions. This variant is present in population databases (rs377114983, gnomAD 0.03%). -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 27, 2020

The p.P121L variant (also known as c.362C>T), located in coding exon 4 of the CHRNA4 gene, results from a C to T substitution at nucleotide position 362. The proline at codon 121 is replaced by leucine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.97

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.59

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.91

Eigen

Pathogenic

0.80

Eigen_PC

Pathogenic

0.69

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

1.0

M_CAP

Pathogenic

0.57

MetaRNN

Pathogenic

0.98

MetaSVM

Uncertain

0.57

MutationTaster

Benign

1.0

PrimateAI

Pathogenic

0.88

PROVEAN

Pathogenic

-9.2

REVEL

Pathogenic

0.95

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.98

MVP

0.97

MPC

1.2

ClinPred

1.0

GERP RS

4.3

Varity_R

0.81

gMVP

0.94

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