rs371888779

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_020549.5(CHAT):​c.1511+5G>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00011 in 1,613,578 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 1 hom. )

Consequence

CHAT
NM_020549.5 splice_region, intron

Scores

2
Splicing: ADA: 0.7125
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.10

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: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.77).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHATNM_020549.5 linkc.1511+5G>A splice_region_variant, intron_variant Intron 10 of 14 ENST00000337653.7 NP_065574.4 P28329-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHATENST00000337653.7 linkc.1511+5G>A splice_region_variant, intron_variant Intron 10 of 14 1 NM_020549.5 ENSP00000337103.2 P28329-1

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152196
Hom.:
0
Cov.:
32
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:
0.000207
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000176
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000104
AC:
26
AN:
249384
AF XY:
0.000140
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000869
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.000187
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.000112
AC:
164
AN:
1461382
Hom.:
1
Cov.:
31
AF XY:
0.000135
AC XY:
98
AN XY:
726970
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000756
AC:
4
AN:
52942
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000135
AC:
150
AN:
1111990
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
9
18
26
35
44
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome 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
GnomAD4 genome
AF:
0.0000920
AC:
14
AN:
152196
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74356
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4828
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000176
AC:
12
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000146
Hom.:
0
Bravo
AF:
0.0000680
EpiCase
AF:
0.00
EpiControl
AF:
0.000296

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Mar 11, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Familial infantile myasthenia Uncertain:1
Oct 05, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 10 of the CHAT gene. It does not directly change the encoded amino acid sequence of the CHAT protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs371888779, 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: 530659). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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
BayesDel_noAF
Benign
-0.77
CADD
Benign
18
DANN
Benign
0.72
PhyloP100
1.1
Mutation Taster
=90/10
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.71
dbscSNV1_RF
Benign
0.46
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: rs371888779; hg19: chr10-50857687; API