5-77426541-CATCT-C

Position:

• chr5-77426541-CATCT-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM4 BS2

The NM_003719.5(PDE8B):​c.2646_2649del​(p.Ser883ThrfsTer18) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000414 in 1,447,800 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: PDE8B NM_003719.5 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

Genes affected

PDE8B (HGNC:8794): (phosphodiesterase 8B) The protein encoded by this gene is a cyclic nucleotide phosphodiesterase (PDE) that catalyzes the hydrolysis of the second messenger cAMP. The encoded protein, which does not hydrolyze cGMP, is resistant to several PDE inhibitors. Defects in this gene are a cause of autosomal dominant striatal degeneration (ADSD). Several transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Jul 2010]

WDR41 (HGNC:25601): (WD repeat domain 41) Contributes to guanyl-nucleotide exchange factor activity. Involved in regulation of autophagy. Located in cytoplasm. Part of guanyl-nucleotide exchange factor complex. Colocalizes with Atg1/ULK1 kinase complex. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM4: Frameshift in the end of transcript resulting in stoplost. Downstream stopcodon found after 964 codons.
• BS2: High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PDE8B	NM_003719.5	c.2646_2649del	p.Ser883ThrfsTer18	frameshift_variant	22/22	ENST00000264917.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PDE8B	ENST00000264917.10	c.2646_2649del	p.Ser883ThrfsTer18	frameshift_variant	22/22	1	NM_003719.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000414 AC: 6 AN: 1447800 Hom.: 0 AF XY: 0.00000416 AC XY: 3 AN XY: 721146

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: 0.00000546

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 05, 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 and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant has not been reported in the literature in individuals affected with PDE8B-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change results in a frameshift in the PDE8B gene (p.Ser883Thrfs*18). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 3 amino acid(s) of the PDE8B protein and extend the protein by 14 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: rs1245608131; hg19: chr5-76722366;