Gene gun is the most effective method used for gene transfer and creation of transgenic plants. This method is also known as Biolistics or Particle bombardment method.
The main principle behind a gene gun is Microcarriers i.e. Tungsten or gold particles are carried by macrocarriers. The apparatus consists of a disc at the top. The macrocarrier is pushed down by rupturing the disc. Located below is the Stopping plate which does not permit the macrocarrier to pass though. However, the microcarriers along with the DNA are propelled at a high speed into the plant material. The DNA segments are released which enters the plant cells and fuses with the genome. This method can also be used for DNA transfers in microorganism and mammalian cells.