Relative Quantities
GenEx lets you calculate the relative expression of target genes compared to a specified sample. Select Relative quantities in the Pre-processing menu in the Data editor to open a dialogue box. Choose the sample that you want to compare all other samples against, and press Apply. The selected sample will get expression 1, samples with higher expression (lower Cq value) will get expression >1, and vice versa.
If the Maximum is chosen, all samles are compared against the sample showing the highest expression (lowest Cq value) within each column (gene) in the following manner.
The alternatives Minimum, Average, and Sample works in the same way by comparing all samples against the least expressed sample, the average expression for each gene, and one given sample respectively. Percentage is usually the preferred choice when one tissue sample was divided into segments that were analyzed separately, e.g. when a tissue sample is sectioned and analyzed by qPCR tomography. It calculates how much of the total mRNA was present in the different sections. Option Nothing simply converts to linear scale. It is usually preferred when there is no common standard sample, but rather one reference sample for each test sample (so called paired study). In such a case, the data is pre-processed first by normalizing the test and reference samples pair-wise using Normalize with reference sample(-s), and then converted to linear scale with Relative quantities option Nothing.