DNases, or deoxyribonucleases, are enzymes that specifically cleave and degrade DNA. In molecular biology, DNase (namely DNase I) is used to degrade DNA in applications such as RNA isolation, reverse transcription preparation, DNA-protein interactions, cell culture, and DNA fragmentation. Clinical uses of DNase include breaking down of mucus to clear up respiratory tracts. Other types of DNases include DNase II (or acid DNase) and shrimp DNase.