A DNA probe is a short, single-stranded piece of DNA that is designed to bind to a specific sequence of nucleotides in a sample. It is often labeled with a fluorescent dye or a radioactive marker, allowing scientists to detect the presence of particular genes or genetic material. DNA probes are widely used in various applications, including genetic testing, forensic analysis, and research in molecular biology. When a DNA probe binds to its complementary sequence, it forms a stable double-stranded structure. This binding can be visualized using techniques such as gel electrophoresis or fluorescence microscopy. By using DNA probes, researchers can identify genetic disorders, track the spread of diseases, and study the genetic makeup of different organisms.