chr4-625705-CTG-C

Position:

• chr4-625705-CTG-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000283.4(PDE6B):​c.80_81del​(p.Leu27GlnfsTer3) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: PDE6B NM_000283.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 4.75

Genes affected

PDE6B (HGNC:8786): (phosphodiesterase 6B) Photon absorption triggers a signaling cascade in rod photoreceptors that activates cGMP phosphodiesterase (PDE), resulting in the rapid hydrolysis of cGMP, closure of cGMP-gated cation channels, and hyperpolarization of the cell. PDE is a peripheral membrane heterotrimeric enzyme made up of alpha, beta, and gamma subunits. This gene encodes the beta subunit. Mutations in this gene result in retinitis pigmentosa and autosomal dominant congenital stationary night blindness. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2009]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 156 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-625705-CTG-C is Pathogenic according to our data. Variant chr4-625705-CTG-C is described in ClinVar as [Pathogenic]. Clinvar id is 1371337.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PDE6B	NM_000283.4	c.80_81del	p.Leu27GlnfsTer3	frameshift_variant	1/22	ENST00000496514.6	NP_000274.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PDE6B	ENST00000496514.6	c.80_81del	p.Leu27GlnfsTer3	frameshift_variant	1/22	1	NM_000283.4	ENSP00000420295	P3
PDE6B	ENST00000255622.10	c.80_81del	p.Leu27GlnfsTer3	frameshift_variant	1/22	1		ENSP00000255622	A1

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 12, 2022

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 1371337). This variant has not been reported in the literature in individuals affected with PDE6B-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Leu27Glnfs*3) in the PDE6B gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PDE6B are known to be pathogenic (PMID: 8394174, 8595886, 22334370). -

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: rs1734053435; hg19: chr4-619494;