UAS regulatory sequences drive expression of four sgRNAs; two target wntD (sgRNA sequences GTGTACTGGTAGTAGCTCATGGG and CATGGGTATTACGAGCACTCTGG) and two target Wnt10 (sgRNA sequences ATGGCGCGATGTGGCCGGTGTGG and CAGAAGCAGCAGCAAGAAGCAGG). The sgRNAs are expressed as a single polycistronic tRNA-gRNA cassette.