At present, DNA probes and nucleic acid amplification techniques are most useful for the characterization of microorganisms for which culture and serological methods are difficult, extremely expensive, or unavailable. DNA-probe based assays are particularly well suited for in situ hibridization in tissue in which the localization and distribition of the microorganisms must be ascertained. Nucleic acid amplification procedures are complex methods that determine whether DNA or RNA from a particular organism is present in the clinical specimen. Because of this complexity, it is useful to assign such methods to one of three general categories; 1) target amplification systems such as polymerase chain reaction (PCR), self-sustaining sequence amplification (3SR), or strand displacement amplification (SDA); 2) probe amplification systems, which include Qfi replicase or ligase chain reaction (LCR); and 3) signal amplification, in which the signal generated from each probe molecule is increased by using compound probes or branched-probe technology (bDNA). Recent advances in molecular technology may revolutionize the clinical microbiology laboratory. These new techniques, their advantages and disadvantages, and some of the recent applications have been discussed in this review. [Journal of Turgut Ozal Medical Center 1997;4(3):329-344
Key Words: Microbiology, diagnostic tests, PCR, LCR, TAS/3SR, SDA, QB replicase, bDNA, DNA probes
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