Master Class: Advances in Molecular Diagnostics: Their Applications and Challenges
Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA
Recent technologic advances have dramatically changed diagnostic testing. With these changes come opportunities, challenges, and ethical dilemmas. For example, nucleic acid amplification combined with fluorescent probes provides a highly sensitive and specific method for pathogen detection. Extensive sequence information deposited in public databases facilitates the design of tests for ever increasing numbers of pathogens. Nucleic acid analysis has been extended to gender determination, speciation of unculturable pathogenic organisms, and detection of antibiotic resistance genes and other genes associated with pathogenesis. These advances permit the early detection of infection and identification of carriers. This high level of sensitivity, however, can yield positive results from vaccination, non-pathogenic organisms, and subclinical infections creating problems for clinicians and regulators. In addition, important issues have arisen from new technologies. These include patenting of microbial organisms and genes, disputes over sample ownership, and profit driven gene discovery. New diagnostic technologies present new challenges to test interpretation, ethical considerations, and the challenge of keeping pace with ever changing technology. Understanding the basic concepts behind these tests enables clinicians to effectively apply and interpret them and to contribute to the ethical dialog regarding their licensing and applications.