20-63350463-G-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BS1

The NM_000744.7(CHRNA4):​c.948C>A​(p.Phe316Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,704 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

5
7
7

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 1.47
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BS1
Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.00000274 (4/1461704) while in subpopulation AFR AF= 0.000119 (4/33480). AF 95% confidence interval is 0.0000398. There are 0 homozygotes in gnomad4_exome. There are 2 alleles in male gnomad4_exome subpopulation. Median coverage is 98. This position pass quality control queck.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CHRNA4NM_000744.7 linkuse as main transcriptc.948C>A p.Phe316Leu missense_variant 5/6 ENST00000370263.9 NP_000735.1
CHRNA4NM_001256573.2 linkuse as main transcriptc.420C>A p.Phe140Leu missense_variant 5/6 NP_001243502.1
CHRNA4NR_046317.2 linkuse as main transcriptn.1157C>A non_coding_transcript_exon_variant 5/6

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CHRNA4ENST00000370263.9 linkuse as main transcriptc.948C>A p.Phe316Leu missense_variant 5/61 NM_000744.7 ENSP00000359285 P1P43681-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461704
Hom.:
0
Cov.:
98
AF XY:
0.00000275
AC XY:
2
AN XY:
727140
show subpopulations
Gnomad4 AFR exome
AF:
0.000119
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
Bravo
AF:
0.00000756

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.26
D
BayesDel_noAF
Pathogenic
0.14
CADD
Benign
21
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.71
D;.
Eigen
Benign
-0.19
Eigen_PC
Benign
-0.091
FATHMM_MKL
Uncertain
0.87
D
LIST_S2
Uncertain
0.93
D;D
M_CAP
Uncertain
0.090
D
MetaRNN
Uncertain
0.68
D;D
MetaSVM
Benign
-0.79
T
MutationAssessor
Benign
1.4
L;.
MutationTaster
Benign
1.0
D
PrimateAI
Pathogenic
0.81
D
PROVEAN
Pathogenic
-4.7
D;.
REVEL
Uncertain
0.47
Sift
Benign
0.53
T;.
Sift4G
Benign
0.36
T;T
Polyphen
0.20
B;.
Vest4
0.94
MutPred
0.55
Gain of helix (P = 0.2059);.;
MVP
0.78
MPC
1.3
ClinPred
1.0
D
GERP RS
3.0
Varity_R
0.44
gMVP
0.72

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.

Other links and lift over

dbSNP: rs121912259; hg19: chr20-61981815; API