Evaluation of Raman Spectroscopy as A Screening Tool to Predict DNA Recovery Potential in Skeletonized Human Remains

The purpose of this study is to determine if Raman spectroscopy can be used as a rapid and non-destructive screening tool to predict DNA recovery potential for bone, and to explore the correlation between the compositional microstructure of bone and preservation of DNA. The two primary structural components of bone are calcium hydroxyapatite and collagen. It is proposed that by analyzing bone using Raman spectroscopy, the presence, state, and distribution of hydroxyapatite and collagen can be measured, which may be useful in predicting if the sample is viable for DNA analysis. The ultimate goal of this study is to develop a screening tool which has the potential to save both money and time for forensic DNA testing of recovered human remains. Previous research demonstrates that the best bones for DNA preservation and recovery are weight-bearing long bones and molar teeth. The diaphysis (shaft) of a long bone is sampled because it is dense, compact bone and contains many osteocytes (nucleated bone cells) that possess DNA. Multiple cuts are made along the diaphysis. However, since the microstructure of bone decomposes in a non-uniform (heterogeneous) manner postmortem, there is no way of knowing which cuttings or regions of the diaphysis contain the most intact microstructure (and presumably the most DNA). The current study hypothesized that by using Raman spectroscopy, the location of the most intact hydroxyapatite and collagen microstructure within the shaft of a long bone can be determined, and that these regions will produce higher yields of DNA (and better-quality DNA)