Gene therapy delivery generally falls into two main categories: viral-mediated and non-viral mediated delivery. Viral-mediated integrative approaches are most commonly used in dividing cells, where delivery is mediated, e.g., through the use of lentiviruses and retroviruses engineered to carry therapeutic DNA into cells. Such viruses have a number of drawbacks, e.g., disruption of the cell's function, the cell’s own machinery may silence expression and payload size limitations. Whereas class II transposons such as piggyBac, Sleeping Beauty, and Tol2 can integrate larger payloads; however, such transposons have a tendency to integrate in areas where active transcription is occurring. Therefore, there is a need in the art for delivery vehicles that provide for delivery of larger coding regions. UC Berkeley researchers have developed a gene delivery system that has a nucleotide sequence encoding an R2 retrotransposon R2 polypeptide that is able to deliver one or more gene products of interest to a eukaryotic cell.