Schemmatic representation of the cyclical nature of the LFC model. Selecting an initial X% limit fold change (1) provides a starting point for the identification of those genes differentially regulated. Genes can then be ranked (2) by a calculation combining fold change and absolute value in order to assign a degree of importance. Validation of the chosen LFC model with RT-PCR (3) and/or the characterization of variance (4) enables the analyst to reexamine the initial LFC model and assign a confidence level to the results. Depending on the dataset, one could redefine the LFC model and repeat the cycle.