DNase I, or Deoxyribonuclease I, is a DNA endonuclease that cleaves phosphodiester linkages indiscriminately to produce oligonucleotide, trinucleotide, or dinucleotide fragments. It can digest single- and double-stranded DNA, chromatin, and DNA-RNA hybrids. Bovine pancreatic DNase I is the variant commonly used in molecular biology applications. The enzyme is dependent on Ca2+ and is activated by Mg2+ or Mn2+.