1.1 This guide covers the identification of bacteriophage M13 used in biotechnology.

1.2 There are many variants of M13 that have been developed specifically for cloning technology. These variants have foreign DNA inserted into the M13 genome, causing the M13 to differ in size and genotype.

1.3 If the M13 is to be used to construct a recombinant molecule, then the criteria described in Section 6 should be used to characterize the newly made DNA.