 mutagenesis  is a process by which the genetic information of an organism is changed in a stable manner, resulting in a mutation. it may occur spontaneously in nature, or as a result of exposure to mutagens. it can also be achieved experimentally using laboratory procedures. in nature mutagenesis can lead to cancer and various heritable diseases, but it is also the driving force of evolution. mutagenesis as a science was developed based on work done by hermann muller, charlotte auerbach and j. m. robson in the first half of the 20th century. ==background== dna may be modified, either naturally or artificially, by a number of physical, chemical and biological agents, resulting in mutations. in 1927, hermann muller first demonstrated mutation with observable changes in the chromosomes can be caused by irradiating fruit flies with x-ray, and lent support to the idea of mutation as the cause of cancer. his contemporary lewis stadler also showed the mutational effect of x-ray on barley in 1928, and ultraviolet (uv) radiation on maize in 1936. in 1940s, charlotte auerbach and j. m. robson, found that mustard gas can also cause mutations in fruit flies. while changes to the chromosome caused by x-ray and mustard gas were readily observable to the early researchers, other changes to the dna induced by other mutagens were not so easily observable, and the mechanism may be complex and takes longer to unravel. for example, soot was suggested to be a cause of cancer as early as 1775, and coal tar was demonstrated to cause cancer in 1915.{{cite journal |author=yamagawa k, ichikawa k |title=experimentelle studie ueber die pathogenese der epithel geschwuelste |journal=mitteilungen aus d
Mutagenesis