ISO 20186-2:2019

Overview - ISO 20186-2:2019 (Molecular IVD pre‑examination for venous whole blood - Isolated genomic DNA)

ISO 20186-2:2019 provides guidance for the pre‑examination phase of molecular in vitro diagnostic (IVD) testing where genomic DNA is the analyte. The standard covers handling, storage, processing and documentation of venous whole blood specimens collected in blood collection tubes, up to the point where the analytical molecular examination begins. It focuses on preserving genomic DNA integrity (including high molecular weight DNA) and reducing degradation/fragmentation during collection, transport, reception, processing and storage.

Key technical topics and requirements

• Specimen collection: selection of appropriate venous whole blood collection tubes and information required about the donor/patient and specimen at collection.
• Stabilization: measures to minimize genomic DNA degradation and fragmentation (note: circulating cell‑free DNA stabilization is excluded and covered in ISO 20186‑3).
• Transport and storage: requirements for safe transport and interim storage before laboratory processing. The document also defines terms such as room temperature (18 °C to 25 °C).
• Laboratory reception and processing: procedures for specimen reception, accessioning, and documentation to maintain chain of custody and specimen traceability.
• Isolation of genomic DNA: guidance on isolation workflows, whether using commercial kits or in‑house protocols; includes recommendations on following examination provider’s instructions when available.
• Quality and quantity assessment: requirements for assessing isolated genomic DNA quality (e.g., suitability for assays requiring HMW DNA) and documenting results.
• Storage of isolated genomic DNA: recommendations for storage practices depending on method of isolation and intended downstream use.
• Terminology and scope limitations: definitions for genomic DNA, HMW DNA (>50 kb on pulsed‑field gel for this document), analyte, pre‑examination processes, and exclusions (capillary blood, dried blood methods, pathogen DNA, and isolated blood cell DNA are not covered).

Practical applications

• Standardizes preanalytical workflows to improve reliability and reproducibility of molecular IVD results.
• Helps laboratories minimize sample degradation that would compromise diagnostics, sequencing, genotyping or other genomic assays-especially those needing high molecular weight DNA.
• Supports biobanks and research institutions in specimen handling and documentation for long‑term storage and data quality.
• Guides IVD developers and manufacturers when qualifying primary sample collection devices and reagents.

Who should use this standard

• Clinical and medical laboratories performing molecular IVD testing
• Laboratory customers and clinicians ordering genomic assays
• IVD developers and manufacturers, biobanks, research organizations and regulatory authorities

Related standards

• ISO 20186 series (see ISO 20186‑3 for circulating cell‑free DNA)
• ISO 15189:2012 (medical laboratory quality and competence)

Keywords: ISO 20186-2, genomic DNA, venous whole blood, pre‑examination processes, molecular IVD, preanalytical, sample handling, DNA isolation, high molecular weight DNA, biobanking.