5-68293836-T-G

Variant names:

• chr5-68293836-T-G
• rs1554051075
• NM_181523.3:c.1425+2T>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_181523.3(PIK3R1):​c.1425+2T>G variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: PIK3R1 NM_181523.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 4.65
• Publications: 1 publications found

Genes affected

PIK3R1 (HGNC:8979): (phosphoinositide-3-kinase regulatory subunit 1) Phosphatidylinositol 3-kinase phosphorylates the inositol ring of phosphatidylinositol at the 3-prime position. The enzyme comprises a 110 kD catalytic subunit and a regulatory subunit of either 85, 55, or 50 kD. This gene encodes the 85 kD regulatory subunit. Phosphatidylinositol 3-kinase plays an important role in the metabolic actions of insulin, and a mutation in this gene has been associated with insulin resistance. Alternative splicing of this gene results in four transcript variants encoding different isoforms. [provided by RefSeq, Jun 2011]

PIK3R1 Gene-Disease associations (from GenCC):

• immunodeficiency 36 with lymphoproliferation

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
• SHORT syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• agammaglobulinemia 7, autosomal recessive

  Inheritance: AR Classification: STRONG, LIMITED Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• activated PI3K-delta syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal agammaglobulinemia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.057931036 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-68293836-T-G is Pathogenic according to our data. Variant chr5-68293836-T-G is described in ClinVar as Pathogenic. ClinVar VariationId is 446498.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIK3R1	NM_181523.3	c.1425+2T>G		splice_donor_variant, intron_variant	Intron 11 of 15	ENST00000521381.6	NP_852664.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIK3R1	ENST00000521381.6	c.1425+2T>G		splice_donor_variant, intron_variant	Intron 11 of 15	1	NM_181523.3	ENSP00000428056.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 27

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Dec 01, 2021

CeGaT Center for Human Genetics Tuebingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 23, 2024

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Identified in multiple patients in published literature with clinical features of APDS, including in one individual as an assumed de novo variant (PMID: 39620215, 35753512, 27221134); Canonical splice site variant predicted to result in an in-frame loss of the adjacent exon in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Different variants affecting the same splice site including, c.1425+1G>A and c.1425+1G>T, have been reported as pathogenic in the published literature and/or at GeneDx in patients with PIK3R1-related features (PMID: 27076228, 27116393, 25133428); This variant is associated with the following publications: (PMID: 30799802, 32181277, 27221134, 33401995, 39620215, 37202577, 34134972, 35753512) -

Immunodeficiency 36 with lymphoproliferation Pathogenic:1

Mar 15, 2023

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Uncertain	0.86	D
PhyloP100		4.6
GERP RS		5.1
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
Splicevardb		3.0
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.96		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1554051075; hg19: chr5-67589664; COSMIC: COSV57135132; COSMIC: COSV57135132;