chr5-68226860-C-T

Position:

• chr5-68226860-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_181523.3(PIK3R1):​c.185C>T​(p.Thr62Ile) 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. 12/21 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)
• Consequence: PIK3R1 NM_181523.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.56

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, PIK3R1
• BP4: Computational evidence support a benign effect (MetaRNN=0.32664084).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIK3R1	NM_181523.3	c.185C>T	p.Thr62Ile	missense_variant	2/16	ENST00000521381.6
PIK3R1	XM_005248542.4	c.185C>T	p.Thr62Ile	missense_variant	2/16
PIK3R1	XM_017009585.3	c.185C>T	p.Thr62Ile	missense_variant	2/16
PIK3R1	XM_047417315.1	c.185C>T	p.Thr62Ile	missense_variant	2/16

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIK3R1	ENST00000521381.6	c.185C>T	p.Thr62Ile	missense_variant	2/16	1	NM_181523.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

SHORT syndrome;C3554689:Agammaglobulinemia 7, autosomal recessive;C4014934:Immunodeficiency 36 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2023

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 62 of the PIK3R1 protein (p.Thr62Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PIK3R1-related conditions. ClinVar contains an entry for this variant (Variation ID: 934762). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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	0.20
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.40
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.43	T;T
Eigen	Benign	0.11
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.96	D
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.33	T;T
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	0.38	N;N
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.79	T
PROVEAN	Benign	-1.7	N;N
REVEL	Benign	0.24
Sift	Uncertain	0.0090	D;D
Sift4G	Uncertain	0.0090	D;D
Polyphen		0.85	P;P
Vest4		0.57
MutPred		0.41		Loss of glycosylation at T62 (P = 0.04);Loss of glycosylation at T62 (P = 0.04);
MVP		0.43
MPC		0.56
ClinPred		0.84	D
GERP RS		4.2
Varity_R		0.38
gMVP		0.46

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: rs1744294827; hg19: chr5-67522688;