rs149976821

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020549.5(CHAT):c.929A>G(p.Asn310Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000511 in 1,566,280 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000042 ( 0 hom. )

Consequence

CHAT
NM_020549.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.31

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHAT	NM_020549.5 link	c.929A>G	p.Asn310Ser	missense_variant	Exon 6 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.929A>G	p.Asn310Ser	missense_variant	Exon 6 of 15	1	NM_020549.5	ENSP00000337103.2		P28329-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152204

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000286

AC:

AN:

174932

Hom.:

AF XY:

0.0000217

AC XY:

AN XY:

92308

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000190

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS 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:

0.00000424

AC:

AN:

1414076

Hom.:

Cov.:

AF XY:

0.00000286

AC XY:

AN XY:

698792

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000133

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000170

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152204

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74356

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Familial infantile myasthenia

Uncertain:1

Aug 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 310 of the CHAT protein (p.Asn310Ser). This variant is present in population databases (rs149976821, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with CHAT-related conditions. ClinVar contains an entry for this variant (Variation ID: 461465). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CHAT protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.14

BayesDel_noAF

Benign

-0.15

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.62

.;.;.;D;.

Eigen

Uncertain

0.55

Eigen_PC

Uncertain

0.52

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.90

.;.;D;D;D

M_CAP

Benign

0.067

MetaRNN

Uncertain

0.69

D;D;D;D;D

MetaSVM

Uncertain

0.28

MutationAssessor

Uncertain

2.2

.;.;.;M;.

PrimateAI

Uncertain

0.59

PROVEAN

Uncertain

-3.2

D;D;D;D;D

REVEL

Uncertain

0.62

Sift

Benign

0.26

T;T;T;T;T

Sift4G

Benign

0.20

T;T;T;T;T

Polyphen

0.99

.;.;.;D;.

Vest4

0.65

MVP

0.91

MPC

0.73

ClinPred

0.49

GERP RS

5.3

Varity_R

0.53

gMVP

0.39

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over