Overview
EN ISO 22753:2022 - Molecular biomarker analysis - Method for the statistical evaluation of analytical results obtained in testing sub‑sampled groups of genetically modified seeds and grains (ISO 22753:2021, corrected version 2022‑11) provides general requirements and procedures for a group testing strategy to evaluate the content of genetically modified (GM) seeds and grains. Endorsed by CEN, this standard covers qualitative testing of sub‑sampled seed/grain groups followed by statistical evaluation to estimate GM content on a percentage seed/grain basis. It is explicitly not applicable to processed products.
Key topics and requirements
- Principle and scope: Defines the group testing approach that examines whole seeds/grains to avoid overestimation caused by stacked events when using single‑sample quantitative PCR.
- Preparation of groups: Guidance on assembling representative sub‑sample groups from a lot for reliable downstream analysis.
- Detection methods: Selection and requirements for qualitative molecular biomarker assays used on groups (e.g., PCR‑based qualitative tests).
- Statistical evaluation: Procedures to convert qualitative group results into estimates of GM seed/grain percentages, and decision rules for accept/reject criteria.
- Testing plan design: Single‑stage and double‑stage testing plans, including considerations for group size and sampling effort.
- Performance criteria: Requirements for method sensitivity, limit of detection (LOD) estimation for a testing plan, and experimental determination of maximum group size.
- Interpretation and reporting: Guidance on classifying lots (accept/reject), expressing estimated levels, and required test‑report contents.
- Annexes: Informative examples - implementation, LOD estimation, maximum group size determination and terms comparison.
Applications and who uses it
EN ISO 22753:2022 is intended for organizations involved in seed/grain quality and regulatory compliance:
- Seed producers and grain handlers monitoring lot purity
- Analytical laboratories performing molecular biomarker testing and statistical evaluation
- Regulatory and conformity assessment bodies assessing compliance with labeling thresholds
- Quality managers and auditors implementing sampling/testing plans to meet acceptance criteria
Practical applications include purity estimation, testing against a defined accept/reject threshold, and accurate assessment of lots that may contain stacked events where quantitative PCR of single samples can be misleading.
Related standards
- ISO 16577 - Molecular biomarker analysis - Terms and definitions (referenced)
- ISO 21572 - Foodstuffs - Molecular biomarker analysis - Immunochemical methods (referenced)
- Developed by ISO/TC 34 and adopted by CEN/TC 275.
Use keywords: EN ISO 22753:2022, group testing strategy, genetically modified seeds, GM content, molecular biomarker analysis, statistical evaluation, stacked events, qualitative analysis.