10-49619775-C-T

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_020549.5(CHAT):​c.438C>T​(p.Tyr146Tyr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00329 in 1,614,028 control chromosomes in the GnomAD database, including 24 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0020 ( 3 hom., cov: 32)
Exomes 𝑓: 0.0034 ( 21 hom. )

Consequence

CHAT
NM_020549.5 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: 1.81

Publications

2 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: Benign. The variant received -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.55).
BP6
Variant 10-49619775-C-T is Benign according to our data. Variant chr10-49619775-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 261336.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=1.81 with no splicing effect.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00205 (312/152340) while in subpopulation NFE AF = 0.00288 (196/68032). AF 95% confidence interval is 0.00255. There are 3 homozygotes in GnomAd4. There are 141 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 3 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.438C>T p.Tyr146Tyr synonymous_variant Exon 3 of 15 ENST00000337653.7 NP_065574.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.438C>T p.Tyr146Tyr synonymous_variant Exon 3 of 15 1 NM_020549.5 ENSP00000337103.2

Frequencies

GnomAD3 genomes
AF:
0.00206
AC:
314
AN:
152222
Hom.:
3
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000555
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00118
Gnomad ASJ
AF:
0.0158
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.00104
Gnomad MID
AF:
0.0127
Gnomad NFE
AF:
0.00288
Gnomad OTH
AF:
0.00239
GnomAD2 exomes
AF:
0.00243
AC:
609
AN:
251080
AF XY:
0.00239
show subpopulations
Gnomad AFR exome
AF:
0.000616
Gnomad AMR exome
AF:
0.00130
Gnomad ASJ exome
AF:
0.0133
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00116
Gnomad NFE exome
AF:
0.00313
Gnomad OTH exome
AF:
0.00408
GnomAD4 exome
AF:
0.00341
AC:
4991
AN:
1461688
Hom.:
21
Cov.:
32
AF XY:
0.00325
AC XY:
2365
AN XY:
727160
show subpopulations
African (AFR)
AF:
0.000568
AC:
19
AN:
33466
American (AMR)
AF:
0.00145
AC:
65
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.0137
AC:
358
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.000359
AC:
31
AN:
86254
European-Finnish (FIN)
AF:
0.00127
AC:
68
AN:
53358
Middle Eastern (MID)
AF:
0.000705
AC:
4
AN:
5676
European-Non Finnish (NFE)
AF:
0.00376
AC:
4176
AN:
1111992
Other (OTH)
AF:
0.00445
AC:
269
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
302
605
907
1210
1512
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
166
332
498
664
830
<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:
0.00205
AC:
312
AN:
152340
Hom.:
3
Cov.:
32
AF XY:
0.00189
AC XY:
141
AN XY:
74494
show subpopulations
African (AFR)
AF:
0.000553
AC:
23
AN:
41578
American (AMR)
AF:
0.00118
AC:
18
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.0158
AC:
55
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.000415
AC:
2
AN:
4822
European-Finnish (FIN)
AF:
0.00104
AC:
11
AN:
10626
Middle Eastern (MID)
AF:
0.0102
AC:
3
AN:
294
European-Non Finnish (NFE)
AF:
0.00288
AC:
196
AN:
68032
Other (OTH)
AF:
0.00189
AC:
4
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
16
33
49
66
82
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.00348
Hom.:
0
Bravo
AF:
0.00208
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00403
EpiControl
AF:
0.00356

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:2
Dec 18, 2019
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 02, 2018
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:2
Apr 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CHAT: BP4, BP7, BS2 -

Feb 22, 2016
Mayo Clinic Laboratories, Mayo Clinic
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

CHAT-related disorder Benign:1
Jul 10, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Familial infantile myasthenia Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.55
CADD
Benign
5.3
DANN
Benign
0.60
PhyloP100
1.8
Mutation Taster
=99/1
polymorphism

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: rs61731734; hg19: chr10-50827821; API