7-137015901-G-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001006630.2(CHRM2):​c.1036G>T​(p.Val346Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,050 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CHRM2
NM_001006630.2 missense

Scores

16

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.868

Publications

1 publications found
Variant links:
Genes affected
CHRM2 (HGNC:1951): (cholinergic receptor muscarinic 2) The muscarinic cholinergic receptors belong to a larger family of G protein-coupled receptors. The functional diversity of these receptors is defined by the binding of acetylcholine to these receptors and includes cellular responses such as adenylate cyclase inhibition, phosphoinositide degeneration, and potassium channel mediation. Muscarinic receptors influence many effects of acetylcholine in the central and peripheral nervous system. The muscarinic cholinergic receptor 2 is involved in mediation of bradycardia and a decrease in cardiac contractility. Multiple alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.049452156).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRM2NM_001006630.2 linkc.1036G>T p.Val346Leu missense_variant Exon 4 of 4 ENST00000680005.1 NP_001006631.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRM2ENST00000680005.1 linkc.1036G>T p.Val346Leu missense_variant Exon 4 of 4 NM_001006630.2 ENSP00000505686.1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151922
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461128
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
726890
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:
33420
American (AMR)
AF:
0.00
AC:
0
AN:
44658
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39632
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53408
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111554
Other (OTH)
AF:
0.00
AC:
0
AN:
60352
⚠️ 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: 0.375
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:
0.00000658
AC:
1
AN:
151922
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74178
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41404
American (AMR)
AF:
0.00
AC:
0
AN:
15236
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5138
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67930
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
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:
0.0000312
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Dilated Cardiomyopathy, Dominant Uncertain:1
Apr 04, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 478112). This variant has not been reported in the literature in individuals affected with CHRM2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.01%). This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 346 of the CHRM2 protein (p.Val346Leu).

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.65
CADD
Benign
6.9
DANN
Benign
0.77
DEOGEN2
Benign
0.048
T;T;T;T
Eigen
Benign
-0.88
Eigen_PC
Benign
-0.81
LIST_S2
Benign
0.0
.;.;.;T
M_CAP
Benign
0.0070
T
MetaRNN
Benign
0.049
T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.13
N;N;N;N
PhyloP100
0.87
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-0.27
N;N;N;N
Sift
Benign
0.79
T;T;T;T
Sift4G
Benign
0.56
T;T;T;T
Vest4
0.014
ClinPred
0.040
T
GERP RS
-3.0
Varity_R
0.063
gMVP
0.21
Mutation Taster
=97/3
polymorphism

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: rs1455067791; hg19: chr7-136700648; API