Mobile genetic element is broadly any genetic element capable of moving itself, with or without duplication, from one site in a genome to another Mobile genetic elements include plasmids, viruses, transposable genetic elements (transposons), short interspread elements, pathogenicity islands and so on. The term 'transposon' was introduced by $R\; W$ Hedges and $A \;E$ jacob in $1974$, to 'controlling' elements' or jumping genes, discovered by Barbara McClintock $(1950)$ in maize.