IWA 32:2019

This document provides requirements and recommendations to laboratories that perform genetically modified organism (GMO) analyses in cottonseed, leaf, cotton fibre and cotton fibre-derived materials. The following are within the scope of this document: a) identifying the materials to be assessed, based on the probability of obtaining good quality, fit for purpose DNA from the materials in subsequent steps in the cotton cloth production process; b) specifying a method for efficient DNA isolation from cotton and cotton-derived materials described under point a); c) specifying the cotton-specific method(s) to be used as control for amplifiable DNA; d) specifying the screening procedure that provides optimal chances to detect GMOs as a result of the performance of the lowest number of genetically modified (GM) element screening assays. NOTE 1 The protocol allows for the screening of all currently known GM cotton events and is set up in a way that optimizes the probability of also detecting unknown GM cotton events that possibly contain similar DNA sequences. Further information is given in CEN/TS 16707. Sampling is outside of the scope of this document. NOTE 2 A recommended sampling method is given in ISO 6497. General guidance for the sampling of bulk materials or for cotton-based products is available in standards such as ASTM D1441‑12 and CEN/TS 15568.