Fingerprint for GM crops?


Researchers have found a way of producing a fingerprint of a plant's inner biological workings by rapidly analyzing hundreds of the chemical products (metabolites) of biosynthetic pathways within the plant. Although not demonstrated in this study, such an approach could greatly help scientists assess potential differences between GM crops and those produced by conventional breeding.


Scientists have recently begun using large-scale techniques such as DNA arrays and chips to study gene expression, and biochemical tests and gels to study protein levels and activity. But until now, no one has attempted to measure their ultimate products, metabolites, on a large scale. In this issue, Oliver Fiehn and colleagues present a rapid approach for studying plant metabolites and the effects of gene alterations on plant metabolic profiles.


The researchers extracted over 300 metabolites from normal and mutant strains of thale cress (Arabidopsis thalianai), and analyzed them by gas chromatography and mass spectrometry-procedures for separating the compounds and identifying them based on their molecular weights. By comparing the relative concentrations of hundreds of compounds in the strains, the researchers determined the effect of single genetic changes on the metabolic profile of the plants. Alterations in many metabolites were observed in two mutant varieties, demonstrating the power of the approach in identifying and quantifying the effects of genetic changes that might previously have been overlooked.