chr7-56102992-G-C

Position:

• chr7-56102992-G-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4 BS2

The NM_016139.4(CHCHD2):​c.320C>G​(p.Pro107Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: CHCHD2 NM_016139.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.923

Genes affected

CHCHD2 (HGNC:21645): (coiled-coil-helix-coiled-coil-helix domain containing 2) The protein encoded by this gene belongs to a class of eukaryotic CX(9)C proteins characterized by four cysteine residues spaced ten amino acids apart from one another. These residues form disulfide linkages that define a CHCH fold. In response to stress, the protein translocates from the mitochondrial intermembrane space to the nucleus where it binds to a highly conserved 13 nucleotide oxygen responsive element in the promoter of cytochrome oxidase 4I2, a subunit of the terminal enzyme of the electron transport chain. In concert with recombination signal sequence-binding protein J, binding of this protein activates the oxygen responsive element at four percent oxygen. In addition, it has been shown that this protein is a negative regulator of mitochondria-mediated apoptosis. In response to apoptotic stimuli, mitochondrial levels of this protein decrease, allowing BCL2-associated X protein to oligomerize and activate the caspase cascade. Pseudogenes of this gene are found on multiple chromosomes. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2016]

CHCHD2 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.28405732).
• BS2: High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHCHD2	NM_016139.4	c.320C>G	p.Pro107Arg	missense_variant	3/4	ENST00000395422.4	NP_057223.1
CHCHD2	NM_001320327.2	c.320C>G	p.Pro107Arg	missense_variant	3/4		NP_001307256.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHCHD2	ENST00000395422.4	c.320C>G	p.Pro107Arg	missense_variant	3/4	1	NM_016139.4	ENSP00000378812.3
CHCHD2	ENST00000473095.1	n.338C>G		non_coding_transcript_exon_variant	3/3	1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461872 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 08, 2018

This variant is not present in population databases (ExAC no frequency). 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 do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with CHCHD2-related disease. This sequence change replaces proline with arginine at codon 107 of the CHCHD2 protein (p.Pro107Arg). The proline residue is weakly conserved and there is a moderate physicochemical difference between proline and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.56
CADD	Benign	14
DANN	Benign	0.87
DEOGEN2	Benign	0.17	T
Eigen	Benign	-0.63
Eigen_PC	Benign	-0.80
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Benign	0.72	T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.28	T
MetaSVM	Benign	-0.83	T
PrimateAI	Benign	0.30	T
PROVEAN	Uncertain	-2.5	N
REVEL	Benign	0.15
Sift	Benign	0.33	T
Sift4G	Benign	0.094	T
Polyphen		0.88	P
Vest4		0.35
MutPred		0.32		Loss of glycosylation at P107 (P = 0.0184);
MVP		0.53
MPC		0.60
ClinPred		0.72	D
GERP RS		-1.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7
Varity_R		0.063
gMVP		0.38

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: rs1785317244; hg19: chr7-56170685;