5-68226833-T-C

Variant names:

• chr5-68226833-T-C
• rs1561258129
• NM_181523.3:c.158T>C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_181523.3(PIK3R1):​c.158T>C​(p.Ile53Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,864 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: 6.8e-7 (0 hom.)
• Consequence: PIK3R1 NM_181523.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.02

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the PIK3R1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 14 curated pathogenic missense variants (we use a threshold of 10). The gene has 11 curated benign missense variants. Gene score misZ: 2.7206 (below the threshold of 3.09). Trascript score misZ: 3.4358 (above the threshold of 3.09). GenCC associations: The gene is linked to agammaglobulinemia 7, autosomal recessive, autosomal agammaglobulinemia, immunodeficiency 36, SHORT syndrome, activated PI3K-delta syndrome.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIK3R1	NM_181523.3	c.158T>C	p.Ile53Thr	missense_variant	Exon 2 of 16	ENST00000521381.6	NP_852664.1
PIK3R1	XM_005248542.4	c.158T>C	p.Ile53Thr	missense_variant	Exon 2 of 16		XP_005248599.1
PIK3R1	XM_017009585.3	c.158T>C	p.Ile53Thr	missense_variant	Exon 2 of 16		XP_016865074.1
PIK3R1	XM_047417315.1	c.158T>C	p.Ile53Thr	missense_variant	Exon 2 of 16		XP_047273271.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIK3R1	ENST00000521381.6	c.158T>C	p.Ile53Thr	missense_variant	Exon 2 of 16	1	NM_181523.3	ENSP00000428056.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251422 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135888

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461864 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727236

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: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Mar 07, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.158T>C (p.I53T) alteration is located in exon 2 (coding exon 1) of the PIK3R1 gene. This alteration results from a T to C substitution at nucleotide position 158, causing the isoleucine (I) at amino acid position 53 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Uncertain	0.056	T
BayesDel_noAF	Benign	-0.16
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.38	T;T
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.44
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	.;D
M_CAP	Benign	0.021	T
MetaRNN	Uncertain	0.50	T;T
MetaSVM	Benign	-0.91	T
MutationAssessor	Benign	0.20	N;N
PrimateAI	Uncertain	0.71	T
PROVEAN	Benign	-1.6	N;N
REVEL	Benign	0.28
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.0040	D;D
Polyphen		0.78	P;P
Vest4		0.76
MutPred		0.51		Gain of disorder (P = 0.0138);Gain of disorder (P = 0.0138);
MVP		0.72
MPC		0.48
ClinPred		0.76	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.66
gMVP		0.61

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: rs1561258129; hg19: chr5-67522661;