Detection of herbicide-resistant maize by using loopmediated isothermal amplification of the pat selectable marker gene

Abstract

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method that reagents react to under isothermal conditions with high specificity, efficiency and rapidity. We used LAMP for detection of herbicide-resistant maize, which is a widespread genetically modified crop. Pat gene, a widely used selectable marker, was amplified by a set of four special primers that recognized six distinct sequences of the target. We studied the optimized conditions for LAMP using different Mg²⁺, dNTPs, betaine and primers concentrations. Furthermore, we tested the sensitivity and specificity of LAMP as compared to PCR. This work shows that the LAMP method can detect a specific pat gene from herbicide-resistant maize and their test results are consistent with the results of the conventional PCR methods. However, LAMP assay results were found to be more sensitive than the conventional PCR.

Key words: Herbicide-resistant maize, loop-mediated isothermal amplification (LAMP), transgenic maize detection, pat gene.