Why is Mitochondrial DNA Important?
Mitochondrial DNA is important for a number of reasons. 13 of its 37 genes are involved in the process known as oxidative phosphorylation. This is the metabolic pathway that produces adenosine triphosphate (ATP), the main energy source of the cell. The remaining 24 genes are involved in the creation of transfer RNA (tRNA) and ribosomal RNA (rRNA) which help to turn amino acids into proteins.
Mitochondrial DNA also appears to be important for a healthy body as there are a number of genetic disorders associated with changes in mitochondrial genes. Some of these genetic disorders are: -
Cancers - mitochondrial DNA, like nuclear DNA is subject to somatic mutations. These are faults that occur during an individual's lifetime and are not passed down to subsequent generations. Mitochondrial DNA mutations have been found in various cancers including breast, colon, and liver cancers.
Leber hereditary optic neuropathy (an inherited form of vision loss) - four mitochondrial genes, MT-ND1, MT-ND4, MT-ND4L, and MT-ND6 have been linked with this condition. It appears that changes in these genes affect the generation of ATP, although it is unknown why the effects of the mutations are limited to the optic nerve.
Nonsyndromic deafness (hearing loss which is not associated with any other syndromes) - mutations in two mitochondrial genes, MT-RNR1 and MT-TS1 are linked to this disorder. The genes are involved in making different types of RNA.