4-83284533-T-C

Position:

chr4-83284533-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001358921.2(COQ2):c.232A>G(p.Met78Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000165 in 1,576,378 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M78T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 34)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

COQ2
NM_001358921.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3O:2

Conservation

PhyloP100: 4.62

Variant links:

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]

COQ2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.14514425).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COQ2	NM_001358921.2 linkuse as main transcript	c.232A>G	p.Met78Val	missense_variant	1/7	ENST00000647002.2
COQ2	NM_015697.9 linkuse as main transcript	c.382A>G	p.Met128Val	missense_variant	1/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COQ2	ENST00000647002.2 linkuse as main transcript	c.232A>G	p.Met78Val	missense_variant	1/7		NM_001358921.2	P2	Q96H96-1
COQ2	ENST00000311469.9 linkuse as main transcript	c.382A>G	p.Met128Val	missense_variant	1/7	1		A2	Q96H96-4
COQ2	ENST00000311461.7 linkuse as main transcript	c.232A>G	p.Met78Val	missense_variant	1/7	5			Q96H96-3
COQ2	ENST00000503391.5 linkuse as main transcript	c.232A>G	p.Met78Val	missense_variant, NMD_transcript_variant	1/7	2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

151932

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000581

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000495

AC:

AN:

181648

Hom.:

AF XY:

0.0000199

AC XY:

AN XY:

100282

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000594

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000132

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000154

AC:

AN:

1424446

Hom.:

Cov.:

AF XY:

0.0000113

AC XY:

AN XY:

705924

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000243

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000110

Gnomad4 OTH exome

AF:

0.0000170

GnomAD4 genome

AF:

0.0000263

AC:

AN:

151932

Hom.:

Cov.:

AF XY:

0.0000539

AC XY:

AN XY:

74212

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000581

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000279

Hom.:

Bravo

AF:

0.0000151

ExAC

AF:

0.0000433

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:3Other:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Coenzyme Q10 deficiency, primary, 1

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 23, 2022

Variant summary: COQ2 c.382A>G (p.Met128Val) results in a conservative amino acid change in the encoded protein sequence. Three of four in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 5.2e-05 in 212966 control chromosomes (gnomAD). c.382A>G has been reported in the literature in at least two homozygous siblings affected with Multiple System Atrophy (Multiple-System Atrophy Research Collaboration_2013). These individuals were also homozygous for p.Val343Ala, which is considered a benign polymorphism (ClinVar:214217). These data indicate that the variant is likely to be associated with disease. Several publications have examined the functional impact of the variant: the variant could not rescue growth in a COQ2-null yeast strain (Multiple-System Atrophy Research Collaboration_2013); COQ2-null yeast expressing the the variant had decreased expression of other Coenzyme Q genes (COQ6, Desbats_2016); COQ2-null yeast had reduced oxygen consumption rate compared to wild-type (Yasuda_2019). Two ClinVar submitters have assessed the variant since 2014: one classified the variant as VUS, and one as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 23, 2021

The c.382A>G (p.M128V) alteration is located in exon 1 (coding exon 1) of the COQ2 gene. This alteration results from a A to G substitution at nucleotide position 382, causing the methionine (M) at amino acid position 128 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Coenzyme Q10 deficiency, primary, 1;C3714927:Multiple system atrophy 1, susceptibility to

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 04, 2022

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 15, 2022

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. Experimental studies have shown that this missense change affects COQ2 function (PMID: 23758206). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt COQ2 protein function. ClinVar contains an entry for this variant (Variation ID: 60536). This missense change has been observed in individual(s) with multiple system atrophy (PMID: 23758206). This variant is present in population databases (rs778094136, gnomAD 0.07%). This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 128 of the COQ2 protein (p.Met128Val). -

Multiple system atrophy

Other:1

risk factor, no assertion criteria provided

literature only

OMIM

Jul 03, 2014

- -

Coenzyme Q10 deficiency

Other:1

not provided, no classification provided

literature only

GeneReviews

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.25

BayesDel_addAF

Benign

-0.20

BayesDel_noAF

Benign

-0.16

CADD

Benign

DANN

Benign

0.65

DEOGEN2

Benign

0.14

.;.;T

Eigen

Benign

-0.20

Eigen_PC

Benign

-0.23

FATHMM_MKL

Benign

0.43

LIST_S2

Pathogenic

0.98

D;.;D

M_CAP

Pathogenic

0.54

MetaRNN

Benign

0.15

T;T;T

MetaSVM

Benign

-0.61

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Pathogenic

0.85

PROVEAN

Uncertain

-2.6

.;D;N

REVEL

Uncertain

0.35

Sift

Benign

0.10

.;T;T

Sift4G

Benign

0.66

.;T;T

Polyphen

0.13

.;.;B

Vest4

0.73, 0.83

MutPred

0.44

Loss of glycosylation at P73 (P = 0.0474);.;Loss of glycosylation at P73 (P = 0.0474);

MVP

0.63

MPC

0.18

ClinPred

0.12

GERP RS

2.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

gMVP

0.73

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over