Devitalization of transgenic seed that preserves DNA and protein integrity.

Agricultural biotechnology companies have been asked to provide intact transgenic seed to regulatory agencies as reference materials for evaluating transgene and protein detection methods (PCR and immunoassay). Due to intellectual-property and product-stewardship considerations, submission of devitalized seed prior to regulatory approval is preferable in any given country. Commonly used devitalization procedures, such as heating or autoclaving, degrade the protein and/or DNA rendering the seed unfit as a reference material for these tests. A novel method for devitalizing seed was developed that involves hydration, freezing in liquid nitrogen, and lyophilization. The devitalization method described here was found to preserve the transgenic DNA and protein in cotton (Gossypium hirsutum) and maize (Zea mays) seed allowing its use as a reference material for evaluating detection methods.