NM_020549.5:c.1061C>T

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM5PP3_StrongPP5_Very_Strong

The NM_020549.5(CHAT):​c.1061C>T​(p.Thr354Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000341 in 1,613,940 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T354S) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 5.71

Publications

6 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: Pathogenic. The variant received 14 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr10-49627734-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1507294.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.977
PP5
Variant 10-49627735-C-T is Pathogenic according to our data. Variant chr10-49627735-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 523528.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.1061C>T p.Thr354Met missense_variant Exon 7 of 15 ENST00000337653.7 NP_065574.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.1061C>T p.Thr354Met missense_variant Exon 7 of 15 1 NM_020549.5 ENSP00000337103.2

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152236
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251258
AF XY:
0.0000147
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:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000349
AC:
51
AN:
1461704
Hom.:
0
Cov.:
32
AF XY:
0.0000316
AC XY:
23
AN XY:
727158
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.0000459
AC:
51
AN:
1111884
Other (OTH)
AF:
0.00
AC:
0
AN:
60378
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.0000263
AC:
4
AN:
152236
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41468
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68054
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000411
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Familial infantile myasthenia Pathogenic:2
Mar 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 354 of the CHAT protein (p.Thr354Met). This variant is present in population databases (rs769234940, gnomAD 0.005%). This missense change has been observed in individual(s) with congenital myasthenic syndrome with episodic apnea (PMID: 15701560). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 523528). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CHAT protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Mar 08, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Lactic acidosis;C0009952:Febrile seizure (within the age range of 3 months to 6 years);C0016202:Pes planus;C0032290:Aspiration pneumonia;C0035229:Respiratory insufficiency;C0162292:External ophthalmoplegia;C0240421:Progressive muscle weakness;C0520680:Apnea, central sleep;C1834015:Progressive ptosis;C1839888:Decreased activity of the pyruvate dehydrogenase complex;C4317146:Gastroesophageal reflux Pathogenic:1
Jan 01, 2017
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.94
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.42
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.88
.;.;.;D;.
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.85
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.97
.;.;D;D;D
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.1
.;.;.;H;.
PhyloP100
5.7
PrimateAI
Uncertain
0.72
T
PROVEAN
Pathogenic
-5.8
D;D;D;D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;D;D;D;D
Sift4G
Pathogenic
0.0010
D;D;D;D;D
Polyphen
1.0
.;.;.;D;.
Vest4
0.97
MVP
0.98
MPC
0.91
ClinPred
1.0
D
GERP RS
5.3
Varity_R
0.93
gMVP
0.87
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs769234940; hg19: chr10-50835781; API