Mitochondrial DNA (mtDNA)

In the human cell there is DNA in the cell nucleus; the nucleus is a cell component which can be thought of as the ‘control centre’. There is also DNA in the cell mitochondria, which are cell-components commonly thought of as the cell's ‘power-house’, supplying the energy needed for the cell. Generally, when we talk of DNA and when we carry out DNA analyses, we talk of nuclear DNA and not mitochondrial DNA. Mitochondrial DNA is passed from mother to all her children but is not passed on by males. Moreover, MtDNA, as it is abbreviated to, remains relatively unchanged as it is inherited from person to person. MtDNA testing is used in relationship testing and by genealogists in ancestry testing to trace maternal lineage and see whether individuals share the same maternal line. However, an MtDNA test cannot tell you how close a distant a female relative is, only that the same maternal line is shared.

This mtDNA test is useful for genealogists when testing ancestry and was used to identify members of the Russian imperial family by having Prince Philip’s Mtdna tested as he shares the same maternal line as Queen Victoria, a close relative of the Russian Imperial family. Also, MtDNA can be used to identify victims of crimes or disasters. Comparing the MtDNA of an unidentified murder victim to a living maternal relative can be an invaluable tool in identification. MtDNA remains relatively unchanged by environmental factors unlike nuclear DNA, and thus again remains an important tool when analysing DNA of someone who has been dead for a long time and whose nuclear DNA may have altered