8-60865611-A-T

Position:

• chr8-60865611-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP2 PP3

The NM_017780.4(CHD7):​c.8672A>T​(p.Asn2891Ile) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHD7 NM_017780.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.03

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), CHD7. . Gene score misZ 3.2193 (greater than the threshold 3.09). Trascript score misZ 3.9401 (greater than threshold 3.09). GenCC has associacion of gene with Kallmann syndrome, hypogonadotropic hypogonadism 5 with or without anosmia, CHARGE syndrome, hypogonadotropic hypogonadism, Omenn syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.81

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHD7	NM_017780.4	c.8672A>T	p.Asn2891Ile	missense_variant	38/38	ENST00000423902.7	NP_060250.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHD7	ENST00000423902.7	c.8672A>T	p.Asn2891Ile	missense_variant	38/38	5	NM_017780.4	ENSP00000392028	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

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

Labcorp Genetics (formerly Invitae), Labcorp

Feb 10, 2020

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CHD7-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces asparagine with isoleucine at codon 2891 of the CHD7 protein (p.Asn2891Ile). The asparagine residue is highly conserved and there is a large physicochemical difference between asparagine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.82
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.69	D;.
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Pathogenic	0.43	D
MetaRNN	Pathogenic	0.81	D;D
MetaSVM	Uncertain	-0.097	T
MutationAssessor	Benign	2.0	M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-6.1	D;D
REVEL	Uncertain	0.37
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.97	D;.
Vest4		0.77
MutPred		0.41		Loss of disorder (P = 0.0076);.;
MVP		0.93
MPC		0.44
ClinPred		0.99	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.79
gMVP		0.78

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: rs202039728; hg19: chr8-61778170;