NM_020549.5:c.1516G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_ModeratePP5_Moderate

The NM_020549.5(CHAT):​c.1516G>T​(p.Val506Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,702 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 (★). Synonymous variant affecting the same amino acid position (i.e. V506V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

6
9
3

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 8.13

Publications

9 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_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.923
PP5
Variant 10-49651888-G-T is Pathogenic according to our data. Variant chr10-49651888-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 17508.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020549.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHAT
NM_020549.5
MANE Select
c.1516G>Tp.Val506Leu
missense
Exon 11 of 15NP_065574.4
CHAT
NM_001142933.2
c.1270G>Tp.Val424Leu
missense
Exon 12 of 16NP_001136405.2
CHAT
NM_001142929.2
c.1162G>Tp.Val388Leu
missense
Exon 11 of 15NP_001136401.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHAT
ENST00000337653.7
TSL:1 MANE Select
c.1516G>Tp.Val506Leu
missense
Exon 11 of 15ENSP00000337103.2
CHAT
ENST00000395562.2
TSL:1
c.1270G>Tp.Val424Leu
missense
Exon 12 of 16ENSP00000378929.2
CHAT
ENST00000339797.5
TSL:1
c.1162G>Tp.Val388Leu
missense
Exon 11 of 15ENSP00000343486.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152246
Hom.:
0
Cov.:
33
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
250522
AF XY:
0.00
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461456
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
727028
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44674
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86200
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111740
Other (OTH)
AF:
0.00
AC:
0
AN:
60386
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00000657
AC:
1
AN:
152246
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74384
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

ClinVar submissions as Germline

Significance:Likely pathogenic
Revision:criteria provided, single submitter
View on ClinVar
Pathogenic
VUS
Benign
Condition
2
-
-
Familial infantile myasthenia (2)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.60
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.34
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.46
T
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.54
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D
M_CAP
Uncertain
0.22
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Uncertain
0.52
D
MutationAssessor
Benign
2.0
M
PhyloP100
8.1
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
-2.1
N
REVEL
Pathogenic
0.86
Sift
Uncertain
0.017
D
Sift4G
Benign
0.064
T
Polyphen
0.77
P
Vest4
0.82
MutPred
0.77
Loss of methylation at K507 (P = 0.0429)
MVP
0.92
MPC
0.67
ClinPred
0.98
D
GERP RS
5.1
Varity_R
0.80
gMVP
0.77
Mutation Taster
=0/100
disease causing (ClinVar)

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: rs121912817; hg19: chr10-50859934; API