Mitochondrial DNA, or maternal DNA, is used extensively in scientific disciplines and allows researchers to make connections between sample subjects and their ancestors. While both maternity and paternity DNA can be used to provide information about a person, the maternal type has special features that make it especially accurate at describing this relationship. This is because, in its mitochondrial form; it is passed directly from the mother to child without any change. It then goes through mutation at a predictable rate. This type of genetic material is produced by organelles called mitochondria within the nucleus, or membrane enclosed center of a cell. These organelles work to convert food to energy for the cells in the form of a substance called adenosine triphosphate, which every cell in your body needs to keep doing its job.
Due to the location within the cell that mitochondrial DNA is made, it tends to be far more durable than the paternal form, though the latter is more commonly used in criminal investigations. In cases where remains have undergone either decay or other forms of destructive processes, the maternal form is the only referential resource that is recoverable. Additionally, since each cell produces so many copies of this type, it is also much easier to extract reliably. These two facts have led to its use in forensic investigations to help identify the remains of victims.
History is full of evidence of military conflict, and one of the most confounding aspects of it has been the difficulty in identifying soldiers’ remains. Using maternal DNA, scientists can make a definitive connection between the remains of a soldier and a living relative. This tactic has been used for the identification of soldiers from the Vietnam War, which left many families unsure of the fates of their loved ones. A prime example of this type of technology at work is the case of First Lieutenant Michael Blassie, an Air Force soldier that was shot down during Vietnam. His remains were identified by comparing them to his mother and his sister’s DNA.
Mitochondrial Eve is the theoretical ancestor of all modern humans, including you. This means that all humans are related to one another through ancestry from a single female in Africa that, by some estimation, would have lived as much as 200,000 years ago. By using regressive models, the predictable rate of mutation that occurs in this type of genetic material was able to be used to provide a mathematically derived estimate of how long ago the most recent common ancestor of all humans would have lived.
The Neanderthal Connection
Archaeology is a field that has benefited immensely from the study and research into mitochondrial DNA. In an attempt to reconcile the relationship between modern humans and the hominid species known as the Neanderthal, this type of genetic material has revealed much about the relationships between the two. In fact, it has been found that anyone with a recent ancestry outside of continental Africa is, on average, over two percent Neanderthal. This means that interbreeding occurred, and the evidence is likely in your genes.
Mitochondrial DNA is a topic that is likely to continue being at the forefront of genetic science for the near future. Few things in biology port so well to mathematical science and being able to base scientific studies on such a clearly understood biological component has proven to be an exceptionally effective tool for research. Given how central this type of genetic material is to modern science, you are likely to see even more groundbreaking uses for it in years to come.