The Body of Evidence

The English King, Richard III, was killed at the Battle of Bosworth on 22nd August 1485.  Contemporary accounts reveal that he was fighting heroically while pressed on all sides by his enemies, the armed forces of the rebel Henry Tudor (later Henry VII).  Famously (and possibly erroneously) depicted by Shakespeare as a murderous, unscrupulous monster, Richard III was the last English king to be killed in battle.  So why am I writing about a long-dead monarch in a forensics blog?  Keep reading to find out! 

 

An archaeological team from the University of Leicester, in association with Leicester City Council and the Richard III Society, has been excavating the site of a mediaeval Franciscan friary in Leicester called Grey Friars. 

On September 12th 2012, while excavating the choir of Grey Friars church, which is believed to be the burial place of Richard III, archaeologists discovered a grave containing human remains.

Could the remains be Richard III?  We shan’t know the answer, or even whether the question can be answered, until early in 2013.  But forensic science is playing a key part in the identification process.

Here is the link to the most recent article on the discovery, which outlines the scientific techniques being employed.  

The Science of the Search for Richard III

 

I imagine that the ‘ancient DNA’ technique being used is Mitochondrial DNA (mtDNA) analysis. Mitochondria (sing. Mitochondrion) are found in the cytoplasm of cells i.e. outside the nucleus.  They are one of the most important ‘organelles’ of a cell, since they are the site of the chemical reactions of respiration, whereby energy is generated for the needs of the cell.  A typical cell contains about a thousand mitochondria.

Old bones, badly decomposed or charred bodies are often poor sources of nuclear DNA, used in standard DNA profiling.  This is because the nuclear DNA becomes degraded, chemically modified or contaminated, and it is not possible to obtain a profile.  Mitochondrial DNA, although not immune to degradation, is better protected within the cell than nuclear DNA.  Its extreme abundance means there is a much greater chance of some of it surviving for longer.  

Human mtDNA is a circular molecule of DNA.  Most of it does not vary between individuals and therefore cannot be used as a forensic identification tool.  However, in a region of the molecule called the ‘D Loop’ or ‘Control Region’, variation does exist in DNA base sequences between unrelated individuals, which is of forensic value.    

I don’t plan to go into the minutiae of the technique here, but I will mention an important point about the inheritance of mtDNA. 

All brothers and sisters in a family will share the same mtDNA as their mother, but not their father.  They will also share the same mtDNA as their mother’s siblings and their grandmother.  This is because an individual inherits their mtDNA only from their mother.

As a consequence, mtDNA analysis cannot provide a unique identification because many individuals can have the same mtDNA base sequences.  Even between unrelated individuals, mtDNA analysis is not as discriminating as standard DNA profiling. The process itself is also not as straightforward as standard DNA profiling.  But it can generate data when standard DNA profiling fails, and this is the technique's undoubted advantage.

I’m very interested to discover that a (male) potential descendant of Richard III’s sister through the female line has been found, so that his mtDNA base sequences can be compared with the base sequences that, hopefully, will be obtained from the mtDNA of the remains.

It would be great if the scientific team are able to find sufficient evidence from their research to suggest that the remains are Richard III.  Follow me on Twitter @forensicswrite to find out.