DNA polymerase is the most accurate enzyme. It creates an exact copy of your DNA each time, making less than one mistake in a billion bases.
DNA polymerases are molecular motors directing the synthesis of DNA from nucleotides. DNA polymerase plays the central role in the processes of life. It carries the responsibility of duplicating our genetic information. Each time a cell divides, DNA polymerase duplicates all of its DNA, and the cell passes one copy to each daughter cell.
Reference — Structure and mechanism of DNA polymerases By Paul J. Rothwell & Gabriel Waksman, www.informatics.indiana.edu