A small, pre-aggregated example containing recurrent protein-altering
PIK3CA mutations in the TCGA breast invasive carcinoma cohort. Counts are
distinct tumor samples, after reducing TCGA aliquot barcodes to their
16-character sample identifiers.
Usage
data(pik3ca_tcga_brca)Format
A data frame with 26 rows and 6 columns:
- gene
HGNC gene symbol; always
PIK3CA.- position
First affected residue in canonical PIK3CA.
- mutation
Short protein-change label.
- count
Number of distinct TCGA tumor samples.
- variant_class
GDC/MAF variant classification.
- source_protein_position
Original GDC
Protein_position.
Source
Mutation calls: NCI Genomic Data Commons TCGA-BRCA.
Protein coordinates refer to canonical PIK3CA transcript ENST00000263967
and UniProt accession P42336,
length 1,068 amino acids. Prepared on 2026-08-13; the R preparation workflow
and exact GDC manifest are kept under data-raw/ in the source repository.
Details
The source is the open-access GDC TCGA-BRCA masked somatic mutation MAF
collection produced by the Aliquot Ensemble Somatic Variant Merging and
Masking workflow. Only canonical transcript ENST00000263967, directly
protein-altering variants are included. The coordinate is the first affected
residue parsed from HGVSp_Short, and only mutations observed in at least
two distinct samples are retained.
The results shown here are in whole or part based upon data generated by the TCGA Research Network: https://www.cancer.gov/tcga.
Examples
data(pik3ca_tcga_brca)
head(pik3ca_tcga_brca)
#> gene position mutation count variant_class source_protein_position
#> 1 PIK3CA 81 E81K 2 Missense_Mutation 81/1068
#> 2 PIK3CA 88 R88Q 2 Missense_Mutation 88/1068
#> 3 PIK3CA 108 R108H 2 Missense_Mutation 108/1068
#> 4 PIK3CA 110 E110del 2 In_Frame_Del 109/1068
#> 5 PIK3CA 111 K111del 2 In_Frame_Del 111/1068
#> 6 PIK3CA 118 G118D 5 Missense_Mutation 118/1068