Little is known about the frequency of mutations caused by plant transformation and the potential biosafety risks they pose to crop species. Plant transformation is often used for commercial crop breeding by inserting transgenes into the chromosomal DNA of plants. However, transgene insertion is rarely perfect; often includes deletions and rearrangements of host chromosomal DNA. Insertion sites including Agrobacterium tumefaciens, particle bombardment, and ancillary procedures associated with plant transformation often contain extensive chromosomal rearrangements, deletions, shuffling of inserted and chromosomal DNA, and mutations. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Plant transformation is the insertion of a transgene into a plant's genome, which is usually accomplished by infecting plant cells with an unarmed pathogenic organism, Agrobacterium tumefaciens, that contains the transgene, or by using particle bombardment, the bombardment of cells with metal particles carrying the transgene. However, the mechanism by which transgenes insert into host DNA is poorly understood. Insertion of the transgene usually involves tissue culture, which causes the reversion of plant tissues around hormones, antibiotics, and other selective agents and allows the regeneration of an intact plant from a genetically modified cell possessing the transgene. The components of plant transformation include mutagens. It is not well known how infection with pathogens and antibiotics can cause mutations in plant genomes. However, the clearest evidence implying this comes from T-DNA tagging experiments using plant transformation without tissue culture, therefore, transformants emerging from plant transformation procedures are exposed to various known or suspected mutagens. Mutations have been found at the insertion site as a result of Agrobacterium-mediated transformation. Agrobacterium-mediated transformation has been used to create commercial transgenic cultivars. Sbach and his colleagues examined 112 independent insertions in the A thaliana genome and found that the majority of insertions involved small deletions of the plant's DNA at the insertion site. Indeed, 21% (24/112) appeared to be associated with plant chromosomal DNA rearrangement or deletion; although two were confirmed as chromosomal translocations, the remaining 22 were never characterized. Insertion site mutations were found to be generated by particle bombardment. Most particle bombardment insertion events involve the insertion of multiple copies of the transported DNA, which appears to be normal. Due to the minimal number of events, conclusions regarding particle bombardment insertion events are only tentative; however, it appears that transgene integration resulting from particle bombardment is usually accompanied by substantial destruction of plant DNA and insertion of superfluous DNA. Deletions and rearrangements associated with transgene insertion increase the likelihood of changes in plant phenotype. Genome-wide mutations are also associated with plant transformation. Studies suggest that plant transformation procedures introduce hundreds to thousands of genome-wide mutations into the DNA of transgenic plants. Basically, extensive genetic mutations are the result of procedures.