FLPm7 is an engineered variant of the FLP recombinase encoded by the Saccharomyces cerevisiae 2μ plasmid, containing the mutations G5D, A36T, T50A, K82Y, G109N, T176A and R281V relative to FLPG5 (FBrf0213120). The target-site specificity of this variant is altered compared to wild-type FLP recombinase, such that FLPm7 is compatible with the mFRT11-71 target site, a derivative of FRT that contains mutations in its inverted repeats (FBrf0213120, PMID:12547191). FLPm7 mediates recombination between a pair of mFRT11-71 sites. The recombination event results in genetic modification, the nature of which is influenced by the relative orientation (direct or inverted), location and composition of the two target sites. The types of possible modification include deletion of DNA, generation of chromosomal rearrangements and integration of DNA into the genome (reviewed in FBrf0231034).

FLPm7 shows no recombinase activity towards the FRT or mFRT11 target sites in an in vivo excision assay. It shows some cross-reactivity with the mFRT71 site: 8.0% of cells carrying a mFRT71 cassette show an excision event compared to 67.2% of cells carrying a mFRT11-71 cassette.