Horizontal gene transfer
A gene transfer agent or 'GTA' is a virus-like element which contains random pieces of the host chromosome. They are found in most members of the alphaproteobacteria order Rhodobacterales. They are encoded by the host genome. GTAs transfer DNA so frequently that they may have an important role in evolution. A 2010 report found that genes for antibiotic resistance could be transferred by engineering GTAs in the laboratory.