Porcn^tm1.1Jrt

An FRT flanked neomycin cassette followed by a loxP site was inserted in intron 2 and a second loxP site was inserted just downstream of exon 3. Exon 3 is flanked by loxP sites (1154 bp). The resistance cassette was then excised from properly targeted ES cells using flp recombinase and leaving exon 3 flanked by loxP sites. Remaining FRT site 30 bp 5 prime of the 5 prime loxP site (FRT-flanked NeoR cassette excised in vitro). (J:198636)