NM_020549.5:c.403C>T

Variant names:

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_020549.5(CHAT):c.403C>T(p.Pro135Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,994 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 Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. P135P) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.91

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

CHAT links:

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, 0.99

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHAT	NM_020549.5 link	c.403C>T	p.Pro135Ser	missense_variant	Exon 3 of 15	ENST00000337653.7	NP_065574.4	P28329-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHAT	ENST00000337653.7 link	c.403C>T	p.Pro135Ser	missense_variant	Exon 3 of 15	1	NM_020549.5	ENSP00000337103.2		P28329-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1459994

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

726352

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:

AN:

33440

American (AMR)

AF:

0.00

AC:

AN:

44714

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26130

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86204

European-Finnish (FIN)

AF:

0.00

AC:

AN:

52500

Middle Eastern (MID)

AF:

0.000197

AC:

AN:

5082

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111930

Other (OTH)

AF:

0.00

AC:

AN:

60294

⚠️ 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: 0.225

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Rigidity;C0037317:Sleep abnormality;C0151786:Muscle weakness;C0575081:Gait disturbance;C0751837:Gait ataxia;C1836150:Gait imbalance

Uncertain:1

Jan 01, 2017

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.50

BayesDel_addAF

Pathogenic

0.56

BayesDel_noAF

Pathogenic

0.57

CADD

Uncertain

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.84

.;.;.;D;.

Eigen

Pathogenic

0.75

Eigen_PC

Uncertain

0.62

FATHMM_MKL

Uncertain

0.93

LIST_S2

Uncertain

0.96

.;.;D;D;D

M_CAP

Uncertain

0.25

MetaRNN

Pathogenic

0.99

D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.7

.;.;.;H;.

PhyloP100

7.9

PrimateAI

Uncertain

0.60

PROVEAN

Pathogenic

-7.0

D;D;D;D;D

REVEL

Pathogenic

0.95

Sift

Uncertain

0.0090

D;D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;D;D

Polyphen

1.0

.;.;.;D;.

Vest4

0.88

MutPred

0.89

.;.;.;Gain of phosphorylation at P135 (P = 0.0502);.;

MVP

0.98

MPC

0.90

ClinPred

1.0

GERP RS

5.1

Varity_R

0.80

gMVP

0.75

Mutation Taster

=37/63

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over