DNase I is an enzyme that breaks down DNA molecules into smaller fragments. It is produced by various organisms, including humans, and plays a crucial role in cellular processes such as DNA repair and apoptosis, which is the programmed cell death. By cleaving DNA, DNase I helps to remove damaged or unnecessary genetic material from cells. In laboratory settings, DNase I is often used in molecular biology techniques to eliminate DNA contamination from RNA samples or to prepare DNA for analysis. Its ability to degrade DNA makes it a valuable tool in research and clinical applications, including gene therapy and diagnostics.