The following cassette was inserted into intron 1 using a gRNA with CRISPR/Cas9 technology: the CAG promoter, a loxP site flanked STOP cassette, the mouse Zfas1 gene, and poly(A) signal sequence. This creates a conditional-ready allele that will only express Zfas1 after cre-mediated removal of the floxed STOP cassette. (J:294533)