Search: Sequence Constraints
With this window you have some control over the actual sequence of primers or probes. Depending on the search type, you may control different aspects of the sequences. In the example above, the TaqMan probe must have a double H at the 5'-end (no two guanosine nucleotides at the very 5'-end). For siRNA probes the probe is forced to contain the A in the third position from the 5'-end, A at the 3'-end, and no G at the 6th position from the 3'-end. If you don't want a T at the 3'-end of a primer, type "V" in the 3' box in Forward or Reverse Primer space. The ambiguous nucleotide symbols are conveniently displayed in the window.