The combination of data (trace IDs and aliquot barcodes) in a trace ID-to-sample relationship file enables researchers to associate sample IDs/aliquot barcodes with assay results. GSCs transfer these trace ID-to-sample relationship files to the DCC for inclusion in the TCGA data repository for public access. While TCGA data is available in this format, trace ID-to-sample relationship files are no longer a primary source data for TCGA as the project has moved to next generation sequencing methods. BAM files are the new sequence currency. The DCC tracks and provides the relationship between BAM files and biospecimen IDs. Trace files are available for TCGA Glioblastoma multiform (GBM) and Ovarian serous cystadenocarcinoma (OV) projects.