Mitochondrial DNA is the small circular chromosome found inside mitochondria. These organelles, found in all eukaryotic cells, are the powerhouse of the cell.[1] The mitochondria, and thus mitochondrial DNA, are passed exclusively from mother to offspring through the egg cell.Illustration of the location of mitochondrial DNA in human cellsElectron microscopy reveals mitochondrial DNA in discrete foci. Bars: 200 nm. (A) Cytoplasmic section after immunogold labelling with anti-DNA; gold particles marking mtDNA are found near the mitochondrial membrane (black dots in upper right). (B) Whole mount view of cytoplasm after extraction with CSK buffer and immunogold labelling with anti-DNA; mtDNA (marked by gold particles) resists extraction. From Iborra et al., 2004.[jargon][2]
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondriaorganelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus, and, in plants and algae, the DNA also is found in plastids, such as chloroplasts.[3]
Human mitochondrial DNA was the first significant part of the human genome to be sequenced.[4] This sequencing revealed that the human mtDNA includes 16,569 base pairs and encodes 13 proteins. As in other vertebrates, the human mitochondrial genetic code differs slightly from nuclear DNA.[5]
^Hassanin A, An J, Ropiquet A, Nguyen TT, Couloux A (March 2013). "Combining multiple autosomal introns for studying shallow phylogeny and taxonomy of Laurasiatherian mammals: Application to the tribe Bovini (Cetartiodactyla, Bovidae)". Molecular Phylogenetics and Evolution. 66 (3): 766–775. Bibcode:2013MolPE..66..766H. doi:10.1016/j.ympev.2012.11.003. PMID23159894.