Nina Hamelberg

Titel: Analysis of the effect of storage temperature on DNA degradation in historical and forensic material

DNA analyses are used in various scientific disciplines. In forensics, by the means of DNA analyses, victims of accidents or crimes can be identified and perpetrators assigned to crime scenes. In historic anthropology, DNA analyses of skeletal remains are used to reconstruct genealogical trees and to conduct studies on population demographics, which can provide information on the lifestyles of past populations. In this context, it is of great importance that samples containing DNA are properly stored to ensure the preservation of the DNA.

Degradation of DNA is a natural process that can be influenced by several factors. Bacterial degradation, the pH value, UV radiation and the humidity of the storage environment can cause the DNA strands to deteriorate. Another factor with a significant effect on DNA preservation is the ambient temperature, as this can influence the reaction rate of chemical processes and bacterial growth.

My master thesis aims to examine the influence of storage temperature on DNA preservation in skeletal material. For this purpose, skeletal material from the Bronze Age Lichtenstein Cave as well as recent forensic trace material, both stored at -20°C for many years, were used for the investigation. About half year before the actual ancient DNA analysis was performed, samples of each source material were taken and stored at room temperature. Aliquots of each material were further kept at -20°C. By means of various molecular genetic methods including a quantitative evaluation differences in the DNA preservation of the differently stored samples are to be determined.