A rapid analytical method using loop-mediated isothermal amplification (LAMP): visual detection of cry1Ab gene in genetically modified maize seeds and food products.

Abstract

Insect resistance is a predominant trait in the globally approved genetically modified (GM) crops. The cry1Ab transgene is featured in over 25% of globally approved insect resistant GM events including both single as well as stacked trait events. GM maize notably contributes for 87% among the approved GM events with cry1Ab gene. GM detection of cry1Ab gene in maize seeds and food products is important for authentication purpose in the countries where GM maize events with cry1Ab gene such as Bt11, Bt176, MON810 are approved, and for surveillance of unauthorized occurrence of such events in the countries where these are not approved. Cost-efficient and rapid GM detection methods are essential for decentralized monitoring for unauthorized GM events across agricultural fields, border inspections, and food supply chains, and for regulatory compliance enabling quick decision-making. A rapid GM detection method employing loop-mediated isothermal amplification (LAMP) was developed for visual analysis of cry1Ab gene in GM maize. The developed assay showed acceptable specificity, which could reliably detect as low as 0.005% of cry1Ab within 60 min. Practical applicability of this assay was also verified for GM detection in maize containing products. The developed method offers a convenient, rapid and cost-effective tool for checking the cry1Ab gene either for regulatory purpose in the countries where the GM crops with cry1Ab gene are restricted or for confirmatory purpose for the samples with cry1Ab gene whenever required.