Editing Selfish genetic element (section)

=== PiggyBac vectors ===
While many transposable elements seem to do no good for the host, some transposable elements have been "tamed" by molecular biologists so that the elements can be made to insert and excise at the will of the scientist. Such elements are especially useful for doing genetic manipulations, like inserting foreign DNA into the genomes of a variety of organisms.<ref>{{cite journal | vauthors = Ryder E, Russell S | title = Transposable elements as tools for genomics and genetics in Drosophila | journal = Briefings in Functional Genomics & Proteomics | volume = 2 | issue = 1 | pages = 57–71 | date = April 2003 | pmid = 15239944 | doi = 10.1093/bfgp/2.1.57 | doi-access =  }}</ref>

One excellent example of this is [[PiggyBac Transposon System|PiggyBac]], a transposable element that can efficiently move between cloning vectors and chromosomes using a "cut and paste" mechanism.<ref>{{cite journal | vauthors = Fraser MJ, Ciszczon T, Elick T, Bauser C | title = Precise excision of TTAA-specific lepidopteran transposons piggyBac (IFP2) and tagalong (TFP3) from the baculovirus genome in cell lines from two species of Lepidoptera | journal = Insect Molecular Biology | volume = 5 | issue = 2 | pages = 141–51 | date = May 1996 | pmid = 8673264 | doi = 10.1111/j.1365-2583.1996.tb00048.x| s2cid = 42758313 }}</ref> The investigator constructs a PiggyBac element with the desired payload spliced in, and a second element (the PiggyBac transposase), located on another plasmid vector, can be co-transfected into the target cell. The PiggyBac transposase cuts at the inverted terminal repeat sequences located on both ends of the PiggyBac vector and efficiently moves the contents from the original sites and integrates them into chromosomal positions where the sequence TTAA is found. The three things that make PiggyBac so useful are the remarkably high efficiency of this cut-and-paste operation, its ability to take payloads up to 200 kb in size, and its ability to leave a perfectly seamless cut from a genomic site, leaving no sequences or mutations behind.<ref>{{cite journal | vauthors = Yusa K | title = Seamless genome editing in human pluripotent stem cells using custom endonuclease-based gene targeting and the piggyBac transposon | journal = Nature Protocols | volume = 8 | issue = 10 | pages = 2061–78 | date = October 2013 | pmid = 24071911 | doi = 10.1038/nprot.2013.126 | s2cid = 12746945 }}</ref>