Forensic Services

Mitochondrial DNA Analysis

Mitochondria are small sub cellular bodies that are the site of energy production in cells. Each cell contains many hundreds or thousands of mitochondria, each containing a small circular loop of DNA. This DNA, like the DNA in the nucleus of the cell, differs between individuals and can be used for forensic identification, however Mitochondrial DNA (Mt.DNA) is inherited exclusively from the individual's mother.

When and how is it used?

The circular loop of Mt.DNA is more resistant to breakdown than the DNA found in the nucleus and the multiple copies present in each cell mean that this can be a very powerful technique that can be used on samples that would not normally be suitable for DNA analysis. Mt.DNA sequence can be obtained from samples such as bones or hairs that don't have any root material.

What are the benefits of using this technique?

Mt DNA analysis is very useful in body identification cases even when the remains are very old or degraded. As all individuals with the same mother will have matching Mt. DNA sequences it is possible to easily compare unidentified remains to relatives such as siblings.

Are there any limitations in using this technique?

The differences in Mitochondrial DNA sequence between individuals are much less pronounced than the differences found in nuclear DNA. The most common Mt DNA sequence occurs in approximately 1 person in 100. Additionally due to the complex nature of the analysis this process can take several weeks.