Do the primer pairs span introns?
Sometimes it is desirable to select a primer pair that spans intron. In this way, genomic DNA contamination can be closely monitored. Usually a PrimerBank primer pair spans intron because a typical exon is quite small. The primer intron-spanning information will be included in the next version update. If it is important for you to be sure that a primer pair spans intron, you may simply do a BLAST search of the primer pair sequences, or better the amplicon sequences (listed in the primer detail page) against the genomic sequences.
