4-83264275-A-G

Position:

• chr4-83264275-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001358921.2(COQ2):​c.1040T>C​(p.Ile347Thr) 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. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: COQ2 NM_001358921.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.94

Genes affected

COQ2 (HGNC:25223): (coenzyme Q2, polyprenyltransferase) This gene encodes an enzyme that functions in the final steps in the biosynthesis of CoQ (ubiquinone), a redox carrier in the mitochondrial respiratory chain and a lipid-soluble antioxidant. This enzyme, which is part of the coenzyme Q10 pathway, catalyzes the prenylation of parahydroxybenzoate with an all-trans polyprenyl group. Mutations in this gene cause coenzyme Q10 deficiency, a mitochondrial encephalomyopathy, and also COQ2 nephropathy, an inherited form of mitochondriopathy with primary renal involvement. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.883

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COQ2	NM_001358921.2	c.1040T>C	p.Ile347Thr	missense_variant	7/7	ENST00000647002.2	NP_001345850.1
COQ2	NM_015697.9	c.1190T>C	p.Ile397Thr	missense_variant	7/7		NP_056512.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COQ2	ENST00000647002.2	c.1040T>C	p.Ile347Thr	missense_variant	7/7		NM_001358921.2	ENSP00000495761	P2
COQ2	ENST00000311469.9	c.1190T>C	p.Ile397Thr	missense_variant	7/7	1		ENSP00000310873	A2
COQ2	ENST00000503915.5	c.*172T>C		3_prime_UTR_variant, NMD_transcript_variant	7/7	1		ENSP00000427146
COQ2	ENST00000503391.5	c.*176-1620T>C		intron_variant, NMD_transcript_variant		2		ENSP00000426242

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 15, 2024

The c.1190T>C (p.I397T) alteration is located in exon 7 (coding exon 7) of the COQ2 gene. This alteration results from a T to C substitution at nucleotide position 1190, causing the isoleucine (I) at amino acid position 397 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.38
CADD	Uncertain	24
DANN	Uncertain	1.0
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;.
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.88	D;D
MetaSVM	Uncertain	0.64	D
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-4.4	.;D
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0010	.;D
Sift4G	Uncertain	0.0020	.;D
Vest4		0.81
MutPred		0.61		Gain of catalytic residue at I347 (P = 0.0046);.;
MVP		0.86
MPC		0.74
ClinPred		1.0	D
GERP RS		6.2
gMVP		0.67

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-84185428;