The RS(I-CreI) entry in FlyBase represents the recognition site for the I-CreI DNA endonuclease. The recognition site is 19-24bp in length (site includes 5'-AAACGTCGTGAGACAGTTT-3'). Cleavage of the RS(I-CreI) site by I-CreI DNA endonuclease results in a double-strand DNA break (PMID:1398106, PMID:8437585).