Several BLAST search options are supported in the NetAffx™ Analysis Center. These options include the ability to turn on/off the Filter Sequence and Perform Gapped Alignment options, and the ability to select E-values from a drop-down menu. You can choose to BLAST your sequence against a particular target sequence database, or against all of the databases at once. The detailed instructions to perform BLAST search are provided in the Analysis Center Tutorial, Lesson 8.