10-49622143-C-G

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_020549.5(CHAT):​c.745C>G​(p.Leu249Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000628 in 1,553,504 control chromosomes in the GnomAD database, including 7 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/21 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. L249L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0036 ( 2 hom., cov: 32)
Exomes 𝑓: 0.00035 ( 5 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

4
14

Clinical Significance

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

Conservation

PhyloP100: 1.08

Publications

4 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 -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.01505819).
BP6
Variant 10-49622143-C-G is Benign according to our data. Variant chr10-49622143-C-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 210707.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00357 (478/133716) while in subpopulation AFR AF = 0.0129 (463/35972). AF 95% confidence interval is 0.0119. There are 2 homozygotes in GnomAd4. There are 222 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 2 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.745C>G p.Leu249Val missense_variant Exon 5 of 15 ENST00000337653.7 NP_065574.4 P28329-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.745C>G p.Leu249Val missense_variant Exon 5 of 15 1 NM_020549.5 ENSP00000337103.2 P28329-1

Frequencies

GnomAD3 genomes
AF:
0.00357
AC:
477
AN:
133586
Hom.:
2
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0129
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000936
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000244
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000162
Gnomad OTH
AF:
0.000569
GnomAD2 exomes
AF:
0.000788
AC:
198
AN:
251414
AF XY:
0.000603
show subpopulations
Gnomad AFR exome
AF:
0.0102
Gnomad AMR exome
AF:
0.000607
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000615
Gnomad OTH exome
AF:
0.000651
GnomAD4 exome
AF:
0.000351
AC:
498
AN:
1419788
Hom.:
5
Cov.:
36
AF XY:
0.000312
AC XY:
220
AN XY:
705994
show subpopulations
African (AFR)
AF:
0.0121
AC:
388
AN:
32164
American (AMR)
AF:
0.000807
AC:
35
AN:
43376
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
24352
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36544
South Asian (SAS)
AF:
0.0000466
AC:
4
AN:
85850
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49782
Middle Eastern (MID)
AF:
0.00127
AC:
7
AN:
5506
European-Non Finnish (NFE)
AF:
0.0000194
AC:
21
AN:
1084738
Other (OTH)
AF:
0.000748
AC:
43
AN:
57476
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
34
67
101
134
168
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.00357
AC:
478
AN:
133716
Hom.:
2
Cov.:
32
AF XY:
0.00343
AC XY:
222
AN XY:
64724
show subpopulations
African (AFR)
AF:
0.0129
AC:
463
AN:
35972
American (AMR)
AF:
0.000935
AC:
12
AN:
12836
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3180
East Asian (EAS)
AF:
0.00
AC:
0
AN:
4346
South Asian (SAS)
AF:
0.000244
AC:
1
AN:
4098
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
8654
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
242
European-Non Finnish (NFE)
AF:
0.0000162
AC:
1
AN:
61788
Other (OTH)
AF:
0.000562
AC:
1
AN:
1780
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
24
48
72
96
120
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:
0.000526
Hom.:
1
Bravo
AF:
0.00347
ESP6500AA
AF:
0.0116
AC:
51
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000972
AC:
118
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

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

Submissions by phenotype

Familial infantile myasthenia Benign:2
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 24, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:2
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Jun 29, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Jan 14, 2015
Genetic Services Laboratory, University of Chicago
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

CHAT-related disorder Benign:1
Oct 12, 2020
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

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

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Benign
-0.26
T
BayesDel_noAF
Benign
-0.14
CADD
Benign
19
DANN
Uncertain
1.0
DEOGEN2
Benign
0.38
.;.;.;T;.
Eigen
Benign
-0.15
Eigen_PC
Benign
0.024
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.73
.;.;T;T;T
MetaRNN
Benign
0.015
T;T;T;T;T
MetaSVM
Uncertain
-0.15
T
MutationAssessor
Benign
1.5
.;.;.;L;.
PhyloP100
1.1
PrimateAI
Benign
0.45
T
PROVEAN
Benign
-1.2
N;N;N;N;N
REVEL
Uncertain
0.32
Sift
Benign
0.11
T;T;T;T;D
Sift4G
Benign
0.10
T;T;T;T;T
Polyphen
0.046
.;.;.;B;.
Vest4
0.26
MVP
0.88
MPC
0.34
ClinPred
0.010
T
GERP RS
4.8
Varity_R
0.40
gMVP
0.47
Mutation Taster
=94/6
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: rs115510708; hg19: chr10-50830189; API