mitochondrial DNA of Homo sapiensHomo sapiens primary cell
The fragmentation was carried out by hydrodynamic shearing system (Covaris, Massachusetts, USA) to generate 180-280bp fragments. Remaining overhangs were converted into blunt ends via exonuclease/polymerase activities and enzymes were removed. After adenylation of 3 ends of DNA fragments, adapter oligonucleotides were ligated. DNA fragments with ligated adapter molecules on both ends were selectively enriched in a PCR reaction. After PCR reaction, library hybridize with Liquid phase with biotin labeled probe, then use magnetic beads with streptomycin to capture the mtDNA. Captured libraries were enriched in a PCR reaction to add index tags to prepare for hybridization.