8-60828682-C-T

Variant names:

• chr8-60828682-C-T
• rs1064793083
• NM_017780.4:c.3398C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 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. 13/22 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:3 U:2
• Conservation: PhyloP100: 7.91
• Publications: 6 publications found

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]

CHD7 Gene-Disease associations (from GenCC):

• CHARGE syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, PanelApp Australia, Broad Center for Mendelian Genomics, ClinGen, G2P
• hypogonadotropic hypogonadism 5 with or without anosmia

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• hypogonadotropic hypogonadism

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Kallmann syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Omenn syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• 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 VariationId is 418124.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHD7	NM_017780.4	c.3398C>T	p.Thr1133Met	missense_variant	Exon 14 of 38	ENST00000423902.7	NP_060250.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHD7	ENST00000423902.7	c.3398C>T	p.Thr1133Met	missense_variant	Exon 14 of 38	5	NM_017780.4	ENSP00000392028.1
CHD7	ENST00000524602.5	c.1717-33547C>T		intron_variant	Intron 2 of 4	1		ENSP00000437061.1
CHD7	ENST00000695853.1	n.3398C>T		non_coding_transcript_exon_variant	Exon 14 of 37			ENSP00000512218.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00 AC: 0 AN: 243928 AF XY: 0.00

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1 Uncertain:1

Dec 06, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Identified in one proband in large cohort of individuals with neurodevelopmental disorders in published literature; however, no further phenotypic information was provided (PMID: 28191889); 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, 30653986, 28191889, 26813943, 38113761, 33057194, 35982159) -

Feb 16, 2025

Laboratory of Genetics, Children's Clinical University Hospital Latvia

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Inborn genetic diseases Pathogenic:1

Feb 29, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

CHARGE syndrome Uncertain:1

Nov 16, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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
PhyloP100		7.9
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
Mutation Taster		=15/85	disease causing (ClinVar)

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

Other links and lift over

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