rs56000199

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_ModerateBP6_ModerateBS2

The NM_000744.7(CHRNA4):​c.1661C>T​(p.Pro554Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000049 in 1,612,174 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. P554P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000053 ( 1 hom., cov: 34)
Exomes 𝑓: 0.000049 ( 0 hom. )

Consequence

CHRNA4
NM_000744.7 missense

Scores

1
17

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 0.597

Publications

6 publications found
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 Gene-Disease associations (from GenCC):
  • autosomal dominant nocturnal frontal lobe epilepsy 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • familial sleep-related hypermotor epilepsy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • autosomal dominant nocturnal frontal lobe epilepsy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -8 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.14760083).
BP6
Variant 20-63349750-G-A is Benign according to our data. Variant chr20-63349750-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 205034.Status of the report is criteria_provided_single_submitter, 1 stars.
BS2
High AC in GnomAd4 at 8 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000744.7. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNA4
NM_000744.7
MANE Select
c.1661C>Tp.Pro554Leu
missense
Exon 5 of 6NP_000735.1
CHRNA4
NM_001256573.2
c.1133C>Tp.Pro378Leu
missense
Exon 5 of 6NP_001243502.1
CHRNA4
NR_046317.2
n.1870C>T
non_coding_transcript_exon
Exon 5 of 6

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNA4
ENST00000370263.9
TSL:1 MANE Select
c.1661C>Tp.Pro554Leu
missense
Exon 5 of 6ENSP00000359285.4
CHRNA4
ENST00000463705.5
TSL:1
n.2309C>T
non_coding_transcript_exon
Exon 4 of 5
CHRNA4
ENST00000467563.3
TSL:1
n.1731C>T
non_coding_transcript_exon
Exon 5 of 6

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152232
Hom.:
1
Cov.:
34
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:
0.000192
Gnomad SAS
AF:
0.000621
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.000955
GnomAD2 exomes
AF:
0.0000766
AC:
19
AN:
247938
AF XY:
0.0000594
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000329
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000270
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000486
AC:
71
AN:
1459824
Hom.:
0
Cov.:
34
AF XY:
0.0000496
AC XY:
36
AN XY:
726146
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44674
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26088
East Asian (EAS)
AF:
0.000176
AC:
7
AN:
39672
South Asian (SAS)
AF:
0.000360
AC:
31
AN:
86202
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52198
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000270
AC:
30
AN:
1111422
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60342
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
4
8
12
16
20
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000525
AC:
8
AN:
152350
Hom.:
1
Cov.:
34
AF XY:
0.0000671
AC XY:
5
AN XY:
74508
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41572
American (AMR)
AF:
0.0000653
AC:
1
AN:
15314
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5190
South Asian (SAS)
AF:
0.000621
AC:
3
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.000945
AC:
2
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000567
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000827
AC:
10
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Autosomal dominant nocturnal frontal lobe epilepsy Benign:1
Jul 01, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.066
BayesDel_addAF
Benign
-0.27
T
BayesDel_noAF
Benign
-0.31
CADD
Benign
11
DANN
Benign
0.73
DEOGEN2
Benign
0.29
T
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.2
FATHMM_MKL
Benign
0.098
N
LIST_S2
Benign
0.56
T
M_CAP
Pathogenic
0.50
D
MetaRNN
Benign
0.15
T
MetaSVM
Benign
-0.57
T
MutationAssessor
Benign
1.6
L
PhyloP100
0.60
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.33
N
REVEL
Benign
0.29
Sift
Benign
0.23
T
Sift4G
Benign
0.41
T
Polyphen
0.017
B
Vest4
0.30
MVP
0.66
MPC
0.41
ClinPred
0.031
T
GERP RS
-0.39
Varity_R
0.037
gMVP
0.25
Mutation Taster
=95/5
polymorphism

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

Other links and lift over

dbSNP: rs56000199; hg19: chr20-61981102; API