Random Mutagenesis

Random Mutagenesis

Random mutagenesis is the easiest way to change the genome of an organism. In this process, a large collection of individuals of the organism, for example seeds of a plant, is targeted with a mutagen, which is something that damages or changes DNA. The key is to use just enough of the mutagen to cause one change in DNA per unit of organism, for example per seed. The collection of organisms is then allowed to grow or multiply and then screened for changes in a specific activity, also known as phenotype. The individual that shows a new phenotype is then isolated, replicated and analyzed to find out exactly where in the genome the change occurred. This technique has actually been used by humans for millennia. The first farmers used natural error rates in DNA replication as the mutagen and screened potential plants for good phenotypes, such as taste, growth rate, and early germination. These early random mutation experiments are now referred to as 'domestication', and the current crop plants are very different from their wild precursors.

This technique is best studied using examples from the literature: