primer88The option Primer must span an exon-exon junction will direct the program to return at least one primer (within a given primer pair) that spans an exon-exon junction. This is useful for limitingPrimer3 was a complete re-implementation of an earlier program: Primer 0.5 (Steve Lincoln, Mark Daly, and Eric S. Lander). Lincoln Stein championed the idea of making Primer3 a software