chr3-179225998-G-A

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP2PP3

The NM_006218.4(PIK3CA):c.2453G>A(p.Arg818His) variant causes a missense change. The variant allele was found at a frequency of 0.0000208 in 1,444,656 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

PIK3CA
NM_006218.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 5.31

Variant links:

Genes affected

PIK3CA (HGNC:8975): (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha) Phosphatidylinositol 3-kinase is composed of an 85 kDa regulatory subunit and a 110 kDa catalytic subunit. The protein encoded by this gene represents the catalytic subunit, which uses ATP to phosphorylate PtdIns, PtdIns4P and PtdIns(4,5)P2. This gene has been found to be oncogenic and has been implicated in cervical cancers. A pseudogene of this gene has been defined on chromosome 22. [provided by RefSeq, Apr 2016]

PIK3CA links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a domain PI3K/PI4K catalytic (size 286) in uniprot entity PK3CA_HUMAN there are 8 pathogenic changes around while only 0 benign (100%) in NM_006218.4

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in the PIK3CA gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 98 curated pathogenic missense variants (we use a threshold of 10). The gene has 13 curated benign missense variants. Gene score misZ: 5.5986 (above the threshold of 3.09). Trascript score misZ: 6.1406 (above the threshold of 3.09). GenCC associations: The gene is linked to hereditary breast carcinoma, vascular malformation, Cowden disease, Cowden syndrome 5, CLOVES syndrome, familial ovarian cancer, megalencephaly-capillary malformation-polymicrogyria syndrome, overgrowth syndrome and/or cerebral malformations due to abnormalities in MTOR pathway genes.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.767

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIK3CA	NM_006218.4 link	c.2453G>A	p.Arg818His	missense_variant	Exon 17 of 21	ENST00000263967.4	NP_006209.2	P42336Q4LE51
PIK3CA	XM_006713658.5 link	c.2453G>A	p.Arg818His	missense_variant	Exon 17 of 21		XP_006713721.1	P42336Q4LE51

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIK3CA	ENST00000263967.4 link	c.2453G>A	p.Arg818His	missense_variant	Exon 17 of 21	2	NM_006218.4	ENSP00000263967.3		P42336

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000808

AC:

AN:

247624

Hom.:

AF XY:

0.00

AC XY:

AN XY:

134360

show subpopulations

Gnomad AFR exome

AF:

0.0000650

Gnomad AMR exome

AF:

0.0000293

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

AF:

0.0000208

AC:

AN:

1444656

Hom.:

Cov.:

AF XY:

0.0000222

AC XY:

AN XY:

719462

show subpopulations

Gnomad4 AFR exome

AF:

0.0000605

Gnomad4 AMR exome

AF:

0.0000450

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000234

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000219

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.0000113

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000122

AC:

ExAC

AF:

0.0000166

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

PIK3CA-related disorder

Uncertain:1

Mar 22, 2024

PreventionGenetics, part of Exact Sciences

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

The PIK3CA c.2453G>A variant is predicted to result in the amino acid substitution p.Arg818His. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0065% of alleles in individuals of African descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Cowden syndrome

Uncertain:1

Aug 16, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 456540). This variant has not been reported in the literature in individuals affected with PIK3CA-related conditions. This variant is present in population databases (rs371049193, gnomAD 0.007%). This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 818 of the PIK3CA protein (p.Arg818His). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.25

BayesDel_addAF

Uncertain

0.11

BayesDel_noAF

Uncertain

0.10

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.78

D;.

Eigen

Uncertain

0.24

Eigen_PC

Uncertain

0.36

FATHMM_MKL

Uncertain

0.96

LIST_S2

Benign

0.84

T;D

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.77

D;D

MetaSVM

Uncertain

-0.20

MutationAssessor

Uncertain

2.2

M;.

PrimateAI

Pathogenic

0.83

PROVEAN

Uncertain

-3.3

D;.

REVEL

Pathogenic

0.67

Sift

Uncertain

0.0090

D;.

Sift4G

Uncertain

0.019

D;.

Polyphen

0.22

B;.

Vest4

0.50

MVP

0.91

MPC

2.7

ClinPred

0.96

GERP RS

5.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.26

gMVP

0.82

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over