The biobanking industry places significant emphasis on ensuring quality control, particularly in terms of standardizing biobanking procedures. However, recent data indicates a 1.5% sample identity error rate.1 These errors or misidentifications can occur at any point, including subject identification, consenting, sampling, processing, storing, analysis and data entry. Ultimately, inaccuracies can negatively impact data interpretation and scientific conclusions. Particularly given the trend toward sample-sharing among institutions, biorepositories benefit from procedures to re-authenticate these samples. Geddes et al. (2015) offer the Beaumont Health System Biobank as a facility with standard operating procedures (SOPs) to identify and correct misidentifications.2
Generally, SOPs require four steps: problem identification, documentation, plan of action and final resolution. The primary resource Beaumont uses is an audit protocol performed by an experienced, multidisciplinary team (two box audits at 162 samples each). The audit workflow includes a comprehensive flowchart for resolving identification issues as well as documentation forms for reporting each step in the process. In the event that the staff fail to confidently identify a misidentified sample after exhausting the available resources for investigation, the biobank discards the specimen. Along with these routine audits, Beaumont uses an iPLEX Pro Sample ID Panel tool with MassARRAY to collect DNA signatures for each patient in the program. These allow the staff to verify sample-donor relationships both as part of the regular workflow for sample utilization and also in the event of misidentifications.
They offer three examples to illustrate how the misidentification SOPs function:
A routine audit revealed serum samples stored in white-capped aliquot tubes reserved for plasma samples. The staff member immediately relocated these specimens to temporary storage and initiated a misidentifications workflow. A sample history audit indicated that the issue was mislabeling, and the team performed a thrombin-clotting test on one daughter aliquot to confirm. Upon getting results, they relabeled the remaining specimens, returned them to the biorepository, and prepared a final report to document the error and resolution.
A staff member performing an audit discovered DNA samples from two patients shared the same sample number. After relocating the samples to temporary storage, the staff used inventory software to review the history of each sample and found missing aliquots from one of the patients during the preceding two weeks. To confirm, they isolated DNA from FFPE tissues from both patients and performed a sample ID assay. At this point, the team relabeled and reported.
The team found a case of samples from two donors with correct de-identified bar code donor aliases (AX numbers) but the same/incorrect biobank alias reference number. They removed the samples and used a sample ID panel to confirm sample-donor relationships before preparing a corrected alias reference number with proper labeling for the mislabeled samples.
Geddes et al. offer these examples and the Beaumont biobank SOPs as a well-established system for discovering and correcting sample identity errors. Rectifying misidentifications with confidence allows biobanks to retain the biospecimens with their requisite fiscal and scientific value.
1 Petrone, J. (2013) “Q&A: RUCDR’s Andy Brooks on the challenges facing biorepositories and the rise of biobank arrays,” BioArray News.
2 Geddes, T.J., et al. (2015) “Utilizing in-house resources to correct sample mixups in a medium throughput biorepository: A case study,” Biopreservation and Biobanking, 14(1) (pp. 71–80), doi: 10.1089/bio.2015.0055.