Table 3.

Appropriateness of the different typing procedures for monitoring defined genetic changes

Type of DNA mutationSuitability of TYPING SYSTEMa:
P1P2P3P4P5P6P7P8G1G2G3G4G5G6G8G9
Replication errors
 Point mutation++++++++++++++
 Slipped-strand phenomena++++++++
 Recombination+++++++++++++
 Inversion+++++
Acquisition of extraneous elements
 Natural transformation+++++++++++++
 Plasmid transfer++++++++++
 Phage transduction or infection++++++++++
 Transposons+++++++++++++
Overall suitability75%88%88%88%13%75%75%50%13%25%75%75%75%100%63%100%
  • a Explanations for the codes P1 to P8 and G1 to G8 are found in Table 1. For many of the mutagenic events described here, there are exceptional situations in which the appropriateness of a given procedure can be seriously questioned. It is not our intention to discuss these situations: this is essentially meant as a somewhat provocative summary of the different possibilities that can be envisaged. The choice of appropriate typing procedures in general cannot be based on the likeliness of one of the events occurring; the bacterial genome still remains a black box. However, on the basis of this table, the systems best suited for molecular typing in general can be picked quite easily. Note that the AFLP procedure has not been included in this evaluation. Plus and minus signs indicate the suitability of a method for detecting a given mutation.