Mitochondrial DNA (mtDNA) has been mapped completely

· MtDNA contains 16,569 base pairs

· The DNA encodes 13 mitochondrial subunits, 22 transfer ribonucleic acids (tRNAs), 2 ribosomal ribonucleic acids (rRNAs), and polypetides. These are found in mitochondrial complexes I, III, IV, and V.

· mtDNA is inherited maternally; therefore, the only way the mtDNA can change is by sequential accumulation of mutations along the maternal lineage.