Twenty-five CEL files (samples) have been imported into Partek Genomics Suite. Sample information must be added to define the grouping and the goals of the experiment.

In this tutorial, the file name (e.g., Down Syndrome-Astrocyte-748-Male-1-U133A.CEL) contains the information about a sample and is separated by hyphens (-). Choosing to split the file name by delimiters will separate the categories into different columns 

The column 5. (Subject) will now be colored red, indicating that it is a random effect. 

Note: More details on Random vs. Fixed Effects can be found later in this tutorial under the section Identifying differentially expressed genes using ANOVA.