rs1064793083

chr8-60828682-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PP2 PP3_Strong PP5

The NM_017780.4(CHD7):c.3398C>T(p.Thr1133Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T1133T) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CHD7 NM_017780.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:2
• Conservation: PhyloP100: 7.91

Genes affected

CHD7 (HGNC:20626): (chromodomain helicase DNA binding protein 7) This gene encodes a protein that contains several helicase family domains. Mutations in this gene have been found in some patients with the CHARGE syndrome. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, CHD7
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 8-60828682-C-T is Pathogenic according to our data. Variant chr8-60828682-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 418124.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=2, Pathogenic=1, Likely_pathogenic=1}. Variant chr8-60828682-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHD7	NM_017780.4	c.3398C>T	p.Thr1133Met	missense_variant	14/38	ENST00000423902.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHD7	ENST00000423902.7	c.3398C>T	p.Thr1133Met	missense_variant	14/38	5	NM_017780.4	P1
CHD7	ENST00000524602.5	c.1717-33547C>T		intron_variant		1
CHD7	ENST00000695853.1	c.3398C>T	p.Thr1133Met	missense_variant, NMD_transcript_variant	14/37

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 29, 2024

The c.3398C>T (p.T1133M) alteration is located in coding exon 13 of the CHD7 gene. This alteration results from a C to T substitution at nucleotide position 3398, causing the threonine (T) at amino acid position 1133 to be replaced by a methionine (M). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This variant was detected as heterozygous in multiple individuals with features consistent with CHARGE syndrome, including two de novo occurrences (Ghaoui, 2015; O'Grady, 2016; Ambry internal data). This amino acid position is highly conserved in available vertebrate species. This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

CHARGE association;C3552553:Hypogonadotropic hypogonadism 5 with or without anosmia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 23, 2023

Identified in one proband in large cohort of individuals with neurodevelopmental disorders in published literature; however, no further phenotypic information was provided (Stessman et al., 2017); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26436962, 26813943, 30653986, 28191889) -

CHARGE association Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 16, 2023

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1133 of the CHD7 protein (p.Thr1133Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of CHD7-related conditions (PMID: 26436962, 30653986). ClinVar contains an entry for this variant (Variation ID: 418124). 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 expected to disrupt CHD7 protein function with a positive 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	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
Cadd	Pathogenic	33
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.61	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.7	H
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-5.6	D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.93
MutPred		0.89		Gain of catalytic residue at T1133 (P = 0.028);
MVP		1.0
MPC		1.8
ClinPred		1.0	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.86
gMVP		0.95

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

Other links and lift over

dbSNP: rs1064793083; hg19: chr8-61741241; COSMIC: COSV71110425; COSMIC: COSV71110425;