chr15-92956550-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001271.4(CHD2):​c.1901T>C​(p.Ile634Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000342 in 1,461,718 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

CHD2
NM_001271.4 missense

Scores

2
4
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.23

Publications

0 publications found
Variant links:
Genes affected
CHD2 (HGNC:1917): (chromodomain helicase DNA binding protein 2) The CHD family of proteins is characterized by the presence of chromo (chromatin organization modifier) domains and SNF2-related helicase/ATPase domains. CHD genes alter gene expression possibly by modification of chromatin structure thus altering access of the transcriptional apparatus to its chromosomal DNA template. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008]
CHD2 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • developmental and epileptic encephalopathy 94
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • Lennox-Gastaut syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myoclonic-astatic epilepsy
    Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.22009322).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHD2NM_001271.4 linkc.1901T>C p.Ile634Thr missense_variant Exon 16 of 39 ENST00000394196.9 NP_001262.3 O14647-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHD2ENST00000394196.9 linkc.1901T>C p.Ile634Thr missense_variant Exon 16 of 39 5 NM_001271.4 ENSP00000377747.4 O14647-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251264
AF XY:
0.0000221
show subpopulations
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:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461718
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727154
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:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111880
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000268), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.395
Heterozygous variant carriers
0
1
1
2
2
3
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
Cov.:
32
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000247
AC:
3

ClinVar

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

Submissions by phenotype

Developmental and epileptic encephalopathy 94 Uncertain:1
Dec 11, 2020
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine with threonine at codon 634 of the CHD2 protein (p.Ile634Thr). The isoleucine residue is highly conserved and there is a moderate physicochemical difference between isoleucine and threonine. This variant is present in population databases (rs757715547, ExAC 0.004%). This variant has been observed in individual(s) with clinical features of childhood-onset epileptic encephalopathy (Invitae). ClinVar contains an entry for this variant (Variation ID: 574837). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C65"). 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
0.14
BayesDel_addAF
Uncertain
0.090
D
BayesDel_noAF
Uncertain
-0.050
CADD
Uncertain
25
DANN
Benign
0.97
DEOGEN2
Benign
0.42
.;T
Eigen
Benign
-0.26
Eigen_PC
Benign
0.015
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.92
D;D
M_CAP
Benign
0.055
D
MetaRNN
Benign
0.22
T;T
MetaSVM
Benign
-0.30
T
MutationAssessor
Benign
-0.46
N;N
PhyloP100
6.2
PrimateAI
Pathogenic
0.81
D
PROVEAN
Benign
-0.76
.;N
REVEL
Uncertain
0.44
Sift
Benign
0.47
.;T
Sift4G
Benign
0.71
T;T
Polyphen
0.010
B;B
Vest4
0.33
MutPred
0.47
Loss of stability (P = 0.008);Loss of stability (P = 0.008);
MVP
0.86
MPC
1.6
ClinPred
0.24
T
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.11
gMVP
0.66
Mutation Taster
=47/53
disease causing

Splicing

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

Publications

Other links and lift over

dbSNP: rs757715547; hg19: chr15-93499780; API