rs1060503186

chr8-60836283-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_017780.4(CHD7):c.3989G>A(p.Arg1330Gln) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1330W) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHD7 NM_017780.4 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

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 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, CHD7
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHD7	NM_017780.4	c.3989G>A	p.Arg1330Gln	missense_variant, splice_region_variant	16/38	ENST00000423902.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHD7	ENST00000423902.7	c.3989G>A	p.Arg1330Gln	missense_variant, splice_region_variant	16/38	5	NM_017780.4	P1
CHD7	ENST00000524602.5	c.1717-25946G>A		intron_variant		1
CHD7	ENST00000695853.1	c.3989G>A	p.Arg1330Gln	missense_variant, splice_region_variant, NMD_transcript_variant	16/37

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

CHARGE syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 12, 2016

In summary, this variant is a novel missense change with uncertain impact on protein function and splicing. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a CHD7-related disease. This sequence change replaces arginine with glutamine at codon 1330 of the CHD7 protein (p.Arg1330Gln). The arginine residue is highly conserved and there is a small physicochemical difference between arginine and glutamine. It also falls at the last nucleotide of exon 16 of the CHD7 coding sequence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.14
Cadd	Pathogenic	36
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.61	D
Eigen	Uncertain	0.67
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Pathogenic	0.41	D
MetaRNN	Uncertain	0.72	D
MetaSVM	Uncertain	0.71	D
MutationAssessor	Benign	-0.46	N
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.2	D
REVEL	Uncertain	0.57
Sift	Benign	0.050	D
Sift4G	Uncertain	0.012	D
Polyphen		1.0	D
Vest4		0.61
MutPred		0.41		Loss of methylation at R1335 (P = 0.1322);
MVP		0.91
MPC		1.8
ClinPred		0.98	D
GERP RS		5.8
Varity_R		0.29
gMVP		0.64

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.25		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.25		Position offset: -44

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060503186; hg19: chr8-61748842;