Final answer:
Nucleic acid probes are used to bind to specific DNA sequences through complementary base pairing. They are tagged with a molecular beacon, like a fluorescent dye or radioactive isotope, to visualize the target DNA, therefore aiding in pathogen detection and genetic research.
Step-by-step explanation:
The term used for a probe attached to a complementary piece of DNA is a nucleic acid probe. These probes are single-stranded fragments of DNA or RNA designed to hybridize, or bind, to a specific sequence of DNA by forming complementary base pairs. To facilitate the detection of these probes, they are labeled with a molecular beacon, such as a radioactive isotope or a fluorescent compound, enabling visualization of the probe's location and, therefore, the target DNA sequence.
Nucleic acid probes play a critical role in the detection of various pathogens, including bacterial and viral species. For example, they are used clinically to detect vaginal pathogens like Candida albicans, Gardnerella vaginalis, and Trichomonas vaginalis. Probes are also essential in genomic research for screening libraries to find genes of interest. Furthermore, they are invaluable in diagnosing genetic disorders by identifying specific mutations within the genes, such as mutations in the beta-globin gene which can be indicated by the presence of a colored spot after hybridization.