2-70936045-C-T

Position:

• chr2-70936045-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001692.4(ATP6V1B1):​c.91C>T​(p.Arg31*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,776 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: ATP6V1B1 NM_001692.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: -0.335

Genes affected

ATP6V1B1 (HGNC:853): (ATPase H+ transporting V1 subunit B1) 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 and three B subunits, two G subunits plus the C, D, E, F, and H subunits. The V1 domain contains the ATP catalytic site. The V0 domain consists of five different subunits: a, c, c', c'', and d. Additional isoforms of many of the V1 and V0 subunit proteins are encoded by multiple genes or alternatively spliced transcript variants. This encoded protein is one of two V1 domain B subunit isoforms and is found in the kidney. Mutations in this gene cause distal renal tubular acidosis associated with sensorineural deafness. [provided by RefSeq, Jul 2008]

VAX2 (HGNC:12661): (ventral anterior homeobox 2) This gene encodes a homeobox protein and is almost exclusively expressed in the ventral portion of the retina during development. In mouse studies, this gene was found to be required for the correct formation of the optic fissure and other aspects of retinal development. [provided by RefSeq, Sep 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 28 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-70936045-C-T is Pathogenic according to our data. Variant chr2-70936045-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 12225.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-70936045-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ATP6V1B1	NM_001692.4	c.91C>T	p.Arg31*	stop_gained	1/14	ENST00000234396.10	NP_001683.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ATP6V1B1	ENST00000234396.10	c.91C>T	p.Arg31*	stop_gained	1/14	1	NM_001692.4	ENSP00000234396.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461776 Hom.: 0 Cov.: 37 AF XY: 0.00000413 AC XY: 3 AN XY: 727208

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: 0.00000630

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Renal tubular acidosis with progressive nerve deafness Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Apr 19, 2024	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jan 01, 1999	- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 14, 2024

This sequence change creates a premature translational stop signal (p.Arg31*) in the ATP6V1B1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ATP6V1B1 are known to be pathogenic (PMID: 9916796, 18368028). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with renal tubular acidosis with sensorineural deafness (PMID: 9916796, 23923981). ClinVar contains an entry for this variant (Variation ID: 12225). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	40
DANN	Uncertain	1.0
Eigen	Uncertain	0.45
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Benign	0.56	D
Vest4		0.67
GERP RS		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs121964879; hg19: chr2-71163175; COSMIC: COSV52265379; COSMIC: COSV52265379;