chr1-204409533-C-T

Position:

• chr1-204409533-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_032833.5(PPP1R15B):​c.1879G>A​(p.Val627Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PPP1R15B NM_032833.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.749

Genes affected

PPP1R15B (HGNC:14951): (protein phosphatase 1 regulatory subunit 15B) This gene encodes a protein phosphatase I-interacting protein that promotes the dephosphorylation of eukaryotic translation initiation factor 2A to regulate translation under conditions of cellular stress. The transcribed messenger RNA contains two upstream open reading frames (ORFs) that repress translation of the main protein coding ORF under normal conditions, while the protein coding ORF is expressed at high levels in response to stress. Continual translation of the mRNA under conditions of eukaryotic translation initiation factor 2A inactivation is thought to create a feedback loop for reactivation of the gene during recovery from stress. In addition, it has been shown that this protein plays a role in membrane traffic that is independent of translation and that it is required for exocytosis from erythroleukemia cells. Allelic variants of this gene are associated with microcephaly, short stature, and impaired glucose metabolism. [provided by RefSeq, Feb 2016]

PPP1R15B-AS1 (HGNC:55838): (PPP1R15B and PIK3C2B antisense RNA 1)

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.06102076).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PPP1R15B	NM_032833.5	c.1879G>A	p.Val627Ile	missense_variant	1/2	ENST00000367188.5
PPP1R15B	XM_005245551.6	c.1879G>A	p.Val627Ile	missense_variant	1/3
PPP1R15B	XM_047432518.1	c.1879G>A	p.Val627Ile	missense_variant	1/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PPP1R15B	ENST00000367188.5	c.1879G>A	p.Val627Ile	missense_variant	1/2	1	NM_032833.5	P1
PPP1R15B-AS1	ENST00000443515.1	n.147-25804C>T		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000160 AC: 4 AN: 250386 Hom.: 0 AF XY: 0.0000148 AC XY: 2 AN XY: 135334

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000117

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000342 AC: 5 AN: 1461112 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726796

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000898

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: 9.00e-7

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 27, 2023

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 627 of the PPP1R15B protein (p.Val627Ile). This variant is present in population databases (no rsID available, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with PPP1R15B-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt PPP1R15B protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.074
BayesDel_addAF	Benign	-0.54	T
BayesDel_noAF	Benign	-0.79
CADD	Benign	4.2
DANN	Benign	0.81
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.077	N
M_CAP	Benign	0.0045	T
MetaRNN	Benign	0.061	T
MetaSVM	Benign	-1.0	T
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.25	T
PROVEAN	Benign	0.21	N
REVEL	Benign	0.10
Sift	Benign	0.64	T
Sift4G	Benign	0.64	T
Vest4		0.016
MutPred		0.49		Loss of sheet (P = 0.1158);
MVP		0.19
MPC		0.077
ClinPred		0.039	T
GERP RS		-1.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
gMVP		0.13

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: rs1412526907; hg19: chr1-204378661;