Insertional mutagenesis

In molecular biology, insertional mutagenesis is the creation of mutations of DNA by the addition of one or more base pairs. Such insertional mutations can occur naturally, mediated by viruses or transposons, or can be artificially created for research purposes in the lab. In molecular biology, insertional mutagenesis is the creation of mutations of DNA by the addition of one or more base pairs. Such insertional mutations can occur naturally, mediated by viruses or transposons, or can be artificially created for research purposes in the lab. This is a technique used to study the function of genes. A transposon such as the P element of Drosophila melanogaster is allowed to integrate at random locations in the genome of the organism being studied. Mutants generated by this method are then screened for any unusual phenotypes. If such a phenotype is found then it can be assumed that the insertion has caused the gene relating to the usual phenotype to be inactivated. Because the sequence of the transposon is known, the gene can be identified, either by sequencing the whole genome and searching for the sequence, or using the polymerase chain reaction to amplify specifically that gene.