Non-destructive or not? Radiological effects at the molecular level

Radiology and DNA analysis represent two of the most popular tools for studying mummified remains. Although radiology is often described as a non-destructive technique, concerns have been raised that this is not the case at the molecular level. Radiation can have a range of damaging effects on DNA depending upon the environment, which makes ancient DNA analysis more difficult than it already is. Despite concerns being raised repeatedly, there has yet to be any published research carried out to determine the extent of the problem. This means that there are no clear guidelines for the use of radiological techniques when biomolecular analysis is to be performed on the same sample, and no screening methods to assist in determining the state of preservation of a sample. This paper will outline the damaging effects of radiation on DNA, concentrating on those processes most relevant to mummified tissue. Possible screening methods and their short-comings will also be described with the aim of provoking debate into their potential, and that of any alternatives. As both radiology and genetics are such powerful and widely used methods in archaeological science, simply calling for a halt until the situation is more clear would be foolish. Discussion of appropriate guidelines should therefore be considered a priority.