Systems in place to stop GE contamination

All crop seeds are imported, providing new strains or particular desired characteristics.

Genetically modified organisms are not allowed into the country and are not wanted by many of the markets that buy our food products.

To limit the risk of the incoming seeds being contaminated with genetically modified material, importers select reputable suppliers with good quality assurance systems. The producer's growing area must be far enough from others to prevent cross-pollination and the resulting seeds must be stored so as to prevent mixing.

All seed consignments destined for New Zealand are tested in a lab in Australia or another in the United States. Both have been checked by MAF-approved microbiologists. Overseas testing allows any failed crops to be sent on to another market.

The test is called the Polymerase Chain Reaction (PCR) and is sensitive enough to detect one modified seed among 1000 unmodified seeds. To reach 95 per cent confidence in the result, 3500 seeds are randomly selected from each consignment, ground down and analysed.

The PCR test amplifies the genetic material within the sample by copying regions of the DNA molecule millions of times so the indicators of genetic modification can be seen.

The indicators are called promoters and terminators. They are located at the start and finish of a constructed piece of DNA that has been added to the original seed DNA.

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