(a) The synthetic target site drive constructs contain Cas9 with the germline nanos promoter and 3’UTR, a dsRed marker with a slightly recoded (*) 3xP3 promoter and P10 3’UTR, and a gRNA driven by the U6:3 promoter that targets the synthetic EGFP gene. The two homology arms include the EGFP sequence with its 3xP3 promoter and SV40 3’UTR regions. (b) The split drive contains a dsRed marker gene driven by a 3xP3 promoter together with a SV40 3’UTR, a gRNA expressed by the U6:3 promoter that targets yellow, and two homology arms for yellow. The unlinked supporting element contains Cas9 driven by the nanos promoter with a nanos 3’UTR, and an EGFP marker gene driven by a 3xP3 promoter together with a SV40 3’UTR.