title: Analytical method evaluation and discovery of variation within maize varieties in the context of food safety: transcript profiling and metabolomics.
abstract: Profiling techniques such as microarrays, proteomics, and metabolomics are used widely to assess the overall effects of genetic background, environmental stimuli, growth stage, or transgene expression in plants. To assess the potential regulatory use of these techniques in agricultural biotechnology, we carried out microarray and metabolomic studies of 3 different tissues from 11 conventional maize varieties. We measured technical variations for both microarrays and metabolomics, compared results from individual plants and corresponding pooled samples, and documented variations detected among different varieties with individual plants or pooled samples. Both microarray and metabolomic technologies are reproducible and can be used to detect plant-to-plant and variety-to-variety differences. A pooling strategy lowered sample variations for both microarray and metabolomics while capturing variety-to-variety variation. However, unknown genomic sequences differing between maize varieties might hinder the application of microarrays. High-throughput metabolomics could be useful as a tool for the characterization of transgenic crops. However, researchers will have to take into consideration the impact on the detection and quantitation of a wide range of metabolites on experimental design as well as validation and interpretation of results.
authors.affiliation: DuPont Pioneer, Regulatory Sciences, Wilmington, Delaware 19880, United States.
authors.forename: Weiqing
authors.initials: W
authors.lastname: Zeng
authors.forename: Jan
authors.initials: J
authors.lastname: Hazebroek
authors.forename: Mary
authors.initials: M
authors.lastname: Beatty
authors.forename: Kevin
authors.initials: K
authors.lastname: Hayes
authors.forename: Christine
authors.initials: C
authors.lastname: Ponte
authors.forename: Carl
authors.initials: C
authors.lastname: Maxwell
authors.forename: Cathy Xiaoyan
authors.initials: CX
authors.lastname: Zhong
mesh_terms: D059022:Food Safety; D030841:Food, Genetically Modified / Q000145:classification; D020869:Gene Expression Profiling / Q000379:methods*; D055432:Metabolomics / Q000379:methods*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D030821:Plants, Genetically Modified / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D003313:Zea mays / Q000145:classification / Q000235:genetics* / Q000378:metabolism