NM_017780.4:c.1925delA

Variant names:

• chr8-60781252-GA-G
• rs1554588712
• NM_017780.4:c.1925delA

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_017780.4(CHD7):​c.1925delA​(p.Lys642ArgfsTer69) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000706 in 1,416,080 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: CHD7 NM_017780.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.28
• Publications: 0 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: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-60781252-GA-G is Pathogenic according to our data. Variant chr8-60781252-GA-G is described in ClinVar as Pathogenic. ClinVar VariationId is 529122.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHD7	NM_017780.4	c.1925delA	p.Lys642ArgfsTer69	frameshift_variant	Exon 3 of 38	ENST00000423902.7	NP_060250.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHD7	ENST00000423902.7	c.1925delA	p.Lys642ArgfsTer69	frameshift_variant	Exon 3 of 38	5	NM_017780.4	ENSP00000392028.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.06e-7 AC: 1 AN: 1416080 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 699896

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000312 AC: 1 AN: 32094

American (AMR) AF: 0.00 AC: 0 AN: 36970

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25324

East Asian (EAS) AF: 0.00 AC: 0 AN: 37302

South Asian (SAS) AF: 0.00 AC: 0 AN: 80392

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50912

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5690

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1088532

Other (OTH) AF: 0.00 AC: 0 AN: 58864

⚠️ 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.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

CHARGE syndrome Pathogenic:2

Oct 22, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (ExAC no frequency). For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in CHD7 are known to be pathogenic (PMID: 22461308, 25077900). This variant has been reported in an individual affected with CHARGE syndrome (PMID: 21158681). This sequence change creates a premature translational stop signal (p.Lys642Argfs*69) in the CHD7 gene. It is expected to result in an absent or disrupted protein product.

Apr 30, 2025

3billion

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant is observed at an extremely low frequency in the gnomAD v4.1.0 dataset (total allele frequency: <0.001%). Predicted Consequence/Location: Frameshift: predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. Multiple pathogenic variants are reported downstream of the variant. The variant has been reported to be associated with CHD7-related disorder (ClinVar ID: VCV000529122 / PMID: 21158681). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.3
Mutation Taster		=0/200	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: rs1554588712; hg19: chr8-61693811;