rs759151717

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_020549.5(CHAT):​c.1843A>G​(p.Ile615Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000434 in 1,614,158 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 Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

6
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.48

Publications

1 publications found
Variant links:
Genes affected
CHAT (HGNC:1912): (choline O-acetyltransferase) This gene encodes an enzyme which catalyzes the biosynthesis of the neurotransmitter acetylcholine. This gene product is a characteristic feature of cholinergic neurons, and changes in these neurons may explain some of the symptoms of Alzheimer's disease. Polymorphisms in this gene have been associated with Alzheimer's disease and mild cognitive impairment. Mutations in this gene are associated with congenital myasthenic syndrome associated with episodic apnea. Multiple transcript variants encoding different isoforms have been found for this gene, and some of these variants have been shown to encode more than one isoform. [provided by RefSeq, May 2010]
CHAT Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 6
    Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • presynaptic congenital myasthenic syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.24203384).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.1843A>G p.Ile615Val missense_variant Exon 14 of 15 ENST00000337653.7 NP_065574.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.1843A>G p.Ile615Val missense_variant Exon 14 of 15 1 NM_020549.5 ENSP00000337103.2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152192
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000385
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
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251444
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461848
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727224
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53378
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
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

Exome 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
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152310
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74488
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41576
American (AMR)
AF:
0.00
AC:
0
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.000386
AC:
2
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68008
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
ExAC
AF:
0.00000824
AC:
1
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Familial infantile myasthenia Uncertain:1
Oct 14, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 615 of the CHAT protein (p.Ile615Val). This variant is present in population databases (rs759151717, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with CHAT-related conditions. ClinVar contains an entry for this variant (Variation ID: 461454). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt CHAT protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Uncertain
0.017
T
BayesDel_noAF
Benign
-0.21
CADD
Benign
16
DANN
Uncertain
0.99
DEOGEN2
Benign
0.30
.;.;.;T;.;.
Eigen
Benign
-0.26
Eigen_PC
Benign
-0.15
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.86
.;.;D;D;D;D
M_CAP
Benign
0.068
D
MetaRNN
Benign
0.24
T;T;T;T;T;T
MetaSVM
Benign
-0.29
T
MutationAssessor
Benign
1.8
.;.;.;L;.;.
PhyloP100
4.5
PrimateAI
Benign
0.45
T
PROVEAN
Benign
-0.86
N;N;N;N;N;.
REVEL
Uncertain
0.32
Sift
Uncertain
0.021
D;D;D;T;D;.
Sift4G
Benign
0.11
T;T;T;T;T;.
Polyphen
0.26
.;.;.;B;.;.
Vest4
0.23
MutPred
0.57
.;.;.;Gain of helix (P = 0.2294);.;.;
MVP
0.87
MPC
0.29
ClinPred
0.22
T
GERP RS
3.1
Varity_R
0.40
gMVP
0.50
Mutation Taster
=72/28
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: rs759151717; hg19: chr10-50870694; API