Dcc^{tm1a(NCOM)Mfgc}

The NorCOMM2LS selection cassette element replaces the region between positions 71809619 and 71809509 (U5 to U3) of Chromosome 18 upstream of the targeted exon(s) (Build 38). The cassette is composed of an F3 site followed by AttB1, IRES and LacZ sequences and then a loxP site. This first loxP site is followed by delta TK1, a T2A sequence and Neomycin, under the control of the human beta-actin promoter and PGK polyA. These are followed by a second F3 site and a second loxP site. A third loxP containing cassette is inserted downstream of the targeted exon(s) between positions 71967417 and 71967489 (D5 to D3). It contains the third loxP followed by an FRT site and AttB2 sequence. The targeted critical exon(s) is(are) thus flanked by loxP sites. A floxed allele can be created by flp recombinase expression in mice carrying this allele. Subsequent cre expression results in a knockout mouse. If cre expression occurs without flp expression, a reporter knockout mouse will be created. (J:165964)