14-73962974-AG-A

Position:

• chr14-73962974-AG-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_182476.3(COQ6):​c.1383delG​(p.Ile462fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: COQ6 NM_182476.3 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1 O:1
• Conservation: PhyloP100: 4.06

Genes affected

COQ6 (HGNC:20233): (coenzyme Q6, monooxygenase) The protein encoded by this gene belongs to the ubiH/COQ6 family. It is an evolutionarily conserved monooxygenase required for the biosynthesis of coenzyme Q10 (or ubiquinone), which is an essential component of the mitochondrial electron transport chain, and one of the most potent lipophilic antioxidants implicated in the protection of cell damage by reactive oxygen species. Knockdown of this gene in mouse and zebrafish results in decreased growth due to increased apoptosis. Mutations in this gene are associated with autosomal recessive coenzyme Q10 deficiency-6 (COQ10D6), which manifests as nephrotic syndrome with sensorineural deafness. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jun 2012]

COQ6 (HGNC:):

ENTPD5 (HGNC:3367): (ectonucleoside triphosphate diphosphohydrolase 5 (inactive)) The protein encoded by this gene is similar to E-type nucleotidases (NTPases)/ecto-ATPase/apyrases. NTPases, such as CD39, mediate catabolism of extracellular nucleotides. ENTPD5 contains 4 apyrase-conserved regions which is characteristic of NTPases. [provided by RefSeq, Jan 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0171 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COQ6	NM_182476.3	c.1383delG	p.Ile462fs	frameshift_variant	12/12	ENST00000334571.7	NP_872282.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COQ6	ENST00000334571.7	c.1383delG	p.Ile462fs	frameshift_variant	12/12	1	NM_182476.3	ENSP00000333946.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial steroid-resistant nephrotic syndrome with sensorineural deafness Pathogenic:1 Other:1

Pathogenic, no assertion criteria provided	literature only	OMIM	May 01, 2011	- -
not provided, no classification provided	literature only	GeneReviews	-	- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 12, 2022

ClinVar contains an entry for this variant (Variation ID: 375345). 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 sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. Experimental studies have shown that this frameshift affects COQ6 function (PMID: 24140869). Algorithms developed to predict the effect of variants on protein structure and function are not available or were not evaluated for this variant. This frameshift has been observed in individual(s) with COQ6-related conditions (PMID: 21540551). This variant is not present in population databases (gnomAD no frequency). This sequence change results in a frameshift in the COQ6 gene (p.Ile462Leufs*18). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 7 amino acid(s) of the COQ6 protein and extend the protein by 10 additional amino acid residues. -

Computational scores

Source: dbNSFP v4.3

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: rs1057519352; hg19: chr14-74429677;