rs794729667

Positions:

• chr8-20220382-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_001693.4(ATP6V1B2):​c.1516C>T​(p.Arg506Ter) variant causes a stop gained change involving the alteration of a non-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 Pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ATP6V1B2 NM_001693.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 1.61

Genes affected

ATP6V1B2 (HGNC:854): (ATPase H+ transporting V1 subunit B2) This gene encodes a component of vacuolar ATPase (V-ATPase), a multisubunit enzyme that mediates acidification of eukaryotic intracellular organelles. V-ATPase dependent organelle acidification is necessary for such intracellular processes as protein sorting, zymogen activation, receptor-mediated endocytosis, and synaptic vesicle proton gradient generation. V-ATPase is composed of a cytosolic V1 domain and a transmembrane V0 domain. The V1 domain consists of three A, three B, and two G subunits, as well as a C, D, E, F, and H subunit. The V1 domain contains the ATP catalytic site. The protein encoded by this gene is one of two V1 domain B subunit isoforms and is the only B isoform highly expressed in osteoclasts. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 0.013 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-20220382-C-T is Pathogenic according to our data. Variant chr8-20220382-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 203442.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr8-20220382-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ATP6V1B2	NM_001693.4	c.1516C>T	p.Arg506Ter	stop_gained	14/14	ENST00000276390.7	NP_001684.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ATP6V1B2	ENST00000276390.7	c.1516C>T	p.Arg506Ter	stop_gained	14/14	1	NM_001693.4	ENSP00000276390	P1
ATP6V1B2	ENST00000523482.5	n.5600C>T		non_coding_transcript_exon_variant	11/11	2
ATP6V1B2	ENST00000521442.1	c.101+2100C>T		intron_variant, NMD_transcript_variant		3		ENSP00000430866

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Autosomal dominant deafness - onychodystrophy syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	May 25, 2020	Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss-of-function has been shown to be a mechanism of disease for this gene (PMID: 24913193). (N) 0107 - This gene is known to be associated with autosomal dominant disease. (N) 0205 - Variant is predicted to result in a truncated protein with less than 1/3 of the protein affected (exon 14 of 14). (P) 0251 - Variant is heterozygous. (N) 0301 - Variant is absent from gnomAD. (P) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (N) 0705 - No comparable variants have previous evidence for pathogenicity. Other truncating variants downstream of this variant has not been reported (ClinVar, PMID: 31655144). (N) 0801 - Strong previous evidence of pathogenicity in unrelated individuals where variant has been shown to be de novo. (ClinVar, PMID: 24913193, 28396750, 31581539). (P) 1002 - Moderate functional evidence supporting abnormal protein function, with variant shown to result in reduced ATPase hydrolysis activity (PMID: 24913193). (P) 1208 - Inheritance information for this variant is not currently available. (N) Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -
Pathogenic, no assertion criteria provided	literature only	OMIM	Nov 01, 2014	- -

Neurodevelopmental delay Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille

-

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Feb 06, 2023

Published functional studies demonstrate a damaging effect; ATPase hydrolysis activity was decreased in cells expressing the R506* variant, and a knock-in mouse model incorporating R506* showed changes in brain composition compared to wild type mice (Yuan et al., 2014; Zhao et al., 2019); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is not a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 28396750, 34912366, 32849222, 31257146, 32961450, 24913193, 32873933) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Uncertain	0.87	D
MutationTaster	Benign	1.0	D
Vest4		0.40
GERP RS		4.6

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: rs794729667; hg19: chr8-20077893;