MICER vectors MHPP352i17 (coordinates of homology region 16:74930370-16:74937378 Mb; mouse assembly GRCm38/mm10) and MHPN352i16 (16:97977263-16:97982380 Mb) were used to insert loxP sites proximal to Lipi and distal to Zbtb21. Cre-mediated recombination duplicated the 23 Mb floxed by loxP sites. (J:227899)