Mitochondrial DNA testing has 2 main uses which will here be discussed briefly. This type of DNA is commonly refered to by the shorter MtDNA testing.
Nuclear DNA and Mitochondrial DNA
All cells contain 2 types of DNA. The most abundant is Nuclear DNA. This is the DNA that carries tens of thousands of our genes and by far the most complex. This DNA is found in an organelle known as the nucleus which can be thought of as “the control centre” of the cell. Nuclear DNA has a double helical structure and its complexity has provided decades of research for scientists. This type of DNA is used for paternity DNA tests and most of the DNA tests available nowadays.
Mitochondrial DNA is found in a different part of the cell; the cell mitochondria to be specific. This part of the cell is responsible for producing energy from food necessary for the cell to function and is of course, used for an MtDNA test.
Both these DNAs are found in the same cell and thus, DNA testing either type of DNA is simple and is commonly done using a sterile mouth swab.
Inheritance and mitochondrial DNA testing
MtDNA, or Mitochondrial DNA is passed from any mother to both her male and female children. It is only females that pass on this type of DNA; fathers have MtDNA that they inherited from their mother but do not pass it on to their children. MtDNA has a low mutation rate and generally remains unchanged from generation to generation. That means that two women who share the same DNA have a common maternal ancestor. Mitochondrial DNA can easily be used to test both distant maternal ancestors as well as to establish whether two people share the same mother or any other common maternal line.
Moreover, MtDNA copies are found in greater numbers making it more likely to extract DNA successfully especially in very old remains where nuclear DNA will have been almost completely destroyed.
MtDNA is also important in criminal investigation when a corpse is found. Sometimes identification can be difficult for a number of reasons; perhaps the body has been burned or left to decompose for far too long. Often, it is used to help exclude missing individuals and unidentified remains. Thus, if a body is found, Mitochondrial DNA testing will involve comparing the MtDNA of relatives of a missing person to see whether there is a match.
Maternal lineage testing with MtDNA
The maternal lineage test will allow you to trace the origins of your ancestors from your mother’s side of the family. The results of this test will allow you to identify which areas of the globe your maternal ancestors originated from and their various movements over time.