The shotgun method (also known as shotgun cloning) is a method in cloning genomic DNA. It involves taking the DNA to be cloned and cutting it either using a restriction enzyme or randomly using a physical method to smash the DNA into small pieces. These fragments are then taken together and cloned into a vector. The original DNA can be either genomic DNA (whole genome shotgun cloning) or a clone such as a YAC (yeast artificial chromosome) that contains a large piece of genomic DNA needing to be split into fragments.

If the DNA needs to be in a certain cloning vector, but the vector can only carry small amounts of DNA, then the shotgun method can be used. More commonly, the method is used to generate small fragments of DNA for sequencing. A DNA sequence can be generated at about 600 bases at a time, so...