rs121913287

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PM2PP2PP3_ModeratePP5_Very_Strong

The NM_006218.4(PIK3CA):​c.263G>A​(p.Arg88Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: not found (cov: 32)

Consequence

PIK3CA
NM_006218.4 missense

Scores

9
7
3

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:10O:1

Conservation

PhyloP100: 7.69
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]

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 13 ACMG points.

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, 0.909
PP5
Variant 3-179199088-G-A is Pathogenic according to our data. Variant chr3-179199088-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 376049.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-179199088-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIK3CANM_006218.4 linkc.263G>A p.Arg88Gln missense_variant Exon 2 of 21 ENST00000263967.4 NP_006209.2 P42336Q4LE51
PIK3CAXM_006713658.5 linkc.263G>A p.Arg88Gln missense_variant Exon 2 of 21 XP_006713721.1 P42336Q4LE51

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIK3CAENST00000263967.4 linkc.263G>A p.Arg88Gln missense_variant Exon 2 of 21 2 NM_006218.4 ENSP00000263967.3 P42336

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Cov.:
31
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:10Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Mar 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PIK3CA: PS2:Very Strong, PM2, PS4:Moderate -

Jan 10, 2023
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Identified in a patient with a clinical diagnosis of megalencephaly-capillary malformation with recurrent ketotic hypoglycemia in published literature (McDermott et al., 2018); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 22729224, 28941273) -

Megalencephaly-capillary malformation-polymicrogyria syndrome Pathogenic:2
Aug 30, 2024
Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

mosaic -

Mar 31, 2022
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0101 - Gain of function is a known mechanism of disease in this gene and is associated with Cowden syndrome 5 (MIM#615108) and megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP) (MIM#602501). (I) 0107 - This gene is associated with autosomal dominant disease. In addition, MCAP is often associated with post-zygotic mosaicism (OMIM). (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to glutamine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0603 - Missense variant in a region that is highly intolerant to missense variation (high constraint region in gnomAD). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. It has been identified in MCAP patients, and in most cases, was de novo and confirmed to be a result of post-zygotic mosaicism. It has also been classified as pathogenic by diagnostic laboratories in ClinVar (PMID: 22729224, 29296277, 28941273, 32778138). (SP) 1203 - This variant has been shown to be de novo in the proband (parental status confirmed; by trio analysis). (SP) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

PIK3CA related overgrowth syndrome Pathogenic:1
-
Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Abnormal cerebral morphology Pathogenic:1
-
Diagnostic Laboratory, Strasbourg University Hospital
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Cowden syndrome 5 Pathogenic:1
Feb 03, 2023
Genomic Medicine Lab, University of California San Francisco
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cowden syndrome Pathogenic:1
May 15, 2019
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant has been reported to have conflicting or insufficient data to determine the effect on PIK3CA protein function (PMID: 22949682). This variant has been observed in individuals affected with megalencephaly-capillary malformation syndrome, including (PMID: 22729224, 28941273). In at least one of these individuals, the variant was found to be de novo. ClinVar contains an entry for this variant (Variation ID: 376049). This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with glutamine at codon 88 of the PIK3CA protein (p.Arg88Gln). The arginine residue is highly conserved and there is a small physicochemical difference between arginine and glutamine. -

CLOVES syndrome Pathogenic:1
Jun 01, 2022
Solve-RD Consortium
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: provider interpretation

Variant confirmed as disease-causing by referring clinical team -

Ovarian neoplasm Pathogenic:1
Dec 01, 2018
German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: research

- -

Neoplasm Other:1
Mar 04, 2025
Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital
Significance: -
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.88
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.78
D;.;.
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.76
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.99
D;D;D
M_CAP
Uncertain
0.13
D
MetaRNN
Pathogenic
0.91
D;D;D
MetaSVM
Uncertain
0.30
D
MutationAssessor
Uncertain
2.5
M;.;.
PrimateAI
Uncertain
0.79
T
PROVEAN
Uncertain
-2.9
D;.;D
REVEL
Pathogenic
0.81
Sift
Benign
0.054
T;.;D
Sift4G
Benign
0.063
T;.;D
Polyphen
1.0
D;.;.
Vest4
0.84
MutPred
0.77
Loss of catalytic residue at R88 (P = 0.0883);Loss of catalytic residue at R88 (P = 0.0883);Loss of catalytic residue at R88 (P = 0.0883);
MVP
0.93
MPC
2.0
ClinPred
0.99
D
GERP RS
5.4
Varity_R
0.74
gMVP
0.86

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

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

Other links and lift over

dbSNP: rs121913287; hg19: chr3-178916876; COSMIC: COSV55874568; COSMIC: COSV55874568; API