Abstract
A nonadecanucleotide has been used both as a site specific mutagen to introduce a T leads to A transversion mutation in the human beta-globin gene cloned in pBR322 as well as a probe to screen transformed colonies for the desired mutant. The specificity of the oligonucleotide as a mutagen and as a hybridization probe provide a general method for producing site specific mutations in DNA cloned in plasmid vectors such as pBR322.