چکیده (انگلیسی):

Two-dimensional gel electrophoresis (2-DE) technique is used as a performing technique
to assess the variability of protein expression in crops, and especially soybean endogenous
food allergens, which are a subset of proteins of interest for assessing whether genetically
modified (GM) soybean has a different allergenic profile compared to its non-GM
counterpart.
On top of the biological variability of the 2-DE, which has already been studied by several
laboratories, technical variability has to be evaluated. In this study, several sources of
variability (number of gel replicates, protein extracts, study timings and operators) were
assessed qualitatively and quantitatively on all detectable polypeptide spots as well as on
food allergen spots. Results showed that the major source of variability was the number of
gel replicates. Other sources were minor.
This has a direct practical impact on the laboratory work as this supports the utilization of
three or four gel replicates to get robust results. Furthermore, this implies that the study can
be run over several days, and be performed by several trained operators, without impacting
its reproducibility.
Furthermore, 2-DE could detect a 2-fold change between two samples with an acceptable
rate of false positives (below 7%). This level of sensitivity is acceptable in the context of safety
assessment of GM soybean as the biological variability of proteins in soybean is higher than
the technical variability shown in this study.
Overall, the 2-DE technique is suitable for investigating endogenous food allergen variability
between several soybean seeds, including GM and non-GM counterpart.