DNA hybridization in diagnostic pathology.

DNA hybridization is becoming an important new adjunct to conventional methods for the diagnosis of infectious diseases, inherited conditions, and neoplasia. Applications of this technology require very small quantities of tissue or body fluids because the DNA probes used in the hybridization assays detect minute amounts of homologous DNA sequence in the test material. Under the proper conditions, these DNA probes are absolutely specific for the pathogen or gene being examined, and hybridization with them usually yields objective answers that require little interpretation. The relatively minor inconveniences currently associated with DNA hybridization are related to the use of radioactivity as a detection signal and the time and labor required to obtain diagnostic data. In the future, technical improvements currently being developed and the preparation of new probes for additional human and microbial genes are likely to create an increasingly larger role for DNA hybridization in diagnostic pathology.