rs79914771

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.327G>A​(p.Thr109Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00109 in 1,613,168 control chromosomes in the GnomAD database, including 9 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00073 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0011 ( 9 hom. )

Consequence

CHAT
NM_020549.5 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 3.39

Publications

0 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 10-49616542-G-A is Benign according to our data. Variant chr10-49616542-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 261334.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=3.39 with no splicing effect.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000729 (111/152268) while in subpopulation SAS AF = 0.00373 (18/4820). AF 95% confidence interval is 0.00241. There are 0 homozygotes in GnomAd4. There are 63 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 9 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.327G>A p.Thr109Thr synonymous_variant Exon 2 of 15 ENST00000337653.7 NP_065574.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.327G>A p.Thr109Thr synonymous_variant Exon 2 of 15 1 NM_020549.5 ENSP00000337103.2

Frequencies

GnomAD3 genomes
AF:
0.000730
AC:
111
AN:
152150
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000362
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000982
Gnomad ASJ
AF:
0.00115
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00373
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000808
Gnomad OTH
AF:
0.00191
GnomAD2 exomes
AF:
0.00137
AC:
343
AN:
249492
AF XY:
0.00174
show subpopulations
Gnomad AFR exome
AF:
0.000311
Gnomad AMR exome
AF:
0.000609
Gnomad ASJ exome
AF:
0.00189
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00104
Gnomad OTH exome
AF:
0.00181
GnomAD4 exome
AF:
0.00113
AC:
1644
AN:
1460900
Hom.:
9
Cov.:
31
AF XY:
0.00129
AC XY:
934
AN XY:
726676
show subpopulations
African (AFR)
AF:
0.000120
AC:
4
AN:
33438
American (AMR)
AF:
0.000717
AC:
32
AN:
44656
Ashkenazi Jewish (ASJ)
AF:
0.00130
AC:
34
AN:
26124
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39638
South Asian (SAS)
AF:
0.00570
AC:
490
AN:
86030
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53382
Middle Eastern (MID)
AF:
0.00537
AC:
31
AN:
5768
European-Non Finnish (NFE)
AF:
0.000869
AC:
966
AN:
1111524
Other (OTH)
AF:
0.00141
AC:
85
AN:
60340
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
93
186
280
373
466
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
40
80
120
160
200
<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:
0.000729
AC:
111
AN:
152268
Hom.:
0
Cov.:
33
AF XY:
0.000846
AC XY:
63
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.000361
AC:
15
AN:
41538
American (AMR)
AF:
0.000981
AC:
15
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00115
AC:
4
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00373
AC:
18
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000809
AC:
55
AN:
68020
Other (OTH)
AF:
0.00189
AC:
4
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000956
Hom.:
0
Bravo
AF:
0.000892
Asia WGS
AF:
0.00144
AC:
5
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:2
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Apr 17, 2017
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not provided Benign:2
Mar 19, 2018
Mayo Clinic Laboratories, Mayo Clinic
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

Familial infantile myasthenia Benign:1
Jan 07, 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
13
DANN
Benign
0.64
PhyloP100
3.4
Mutation Taster
=298/2
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: rs79914771; hg19: chr10-50824588; API