Metabolic profiling of transgenic crops for safety assessment

Abstract

Transgenic crop safety cannot be adequately assessed without comprehensive metabolic characterization. This research employed untargeted metabolomics to compare the metabolic profiles of genetically modified maize expressing Bt toxin genes with conventional isogenic counterparts. Samples were collected from field trials conducted at Wellington Institute of Technology research farms between September 2022 and April 2023. Metabolite extraction and analysis utilized liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry platforms. A total of 287 metabolites were identified and quantified across both sample groups. Principal component analysis revealed substantial overlap between transgenic and conventional samples, with the first two components explaining 67.3% of total variance. Only 12 metabolites (4.2%) showed statistically significant differences between groups, all within natural variation ranges reported for conventional maize varieties. No novel or potentially toxic compounds were detected in transgenic samples. Pathway analysis indicated that the genetic modification did not substantially alter primary or secondary metabolic networks. These findings support the substantial equivalence of transgenic Bt maize to conventional varieties at the metabolome level, providing valuable safety data for regulatory assessment.