The recovery of touch DNA from RDX-C4 evidences

Abstract

RDX (Royal Demolition Explosive) is the organic compound with the formula (O2NNCH2)3. It is a white solid material without smell or taste, widely used as an explosive. It is more energetic explosive than TNT, and it was used widely in World War II. The estimated number of RDX-C4 cases in Bahrain ranged between the years 2015–2018 (May) with a total quantity of 370.72 KG in a total number of 38 cases. The effect of explosive RDX-C4 is very massive and can cause many causalities and fatalities among civilians and policemen. These cases consisted of adhesive film with tapes wrapped around RDX-C4 substance (Demolition Charge M112), black batteries, pipes, black bag contained RDX-C4, and in magnetic improvised explosive device (IED). Touch DNA recovery utilized different collection methods, such as nylon swabbing, tape lifting, and direct cutting of certain parts of the samples that were positive of RDX-C4 through DXR Raman Spectrometer. Samples were extracted and purified with magnetic beads chemistry and quantified. Low copy DNA extracts were subjected to a concentration step. DNA extracts were amplified and processed for detection to obtain reliable results using GlobalFiler Amplification PCR kit and run through ABI 3500xL Genetic Analyzer for fragment length determination. We have discovered that RDX-C4 cannot bind to the DNA nor to the solutions used in DNA typing. Thus, it does not cause DNA inhibition or degradation. From this point of view, we were successful in obtaining acceptable and fit results using advanced techniques. This study will be very useful and informative to assist the forensic community in terrorism case applications worldwide as terrorists do not respect geographical boundaries nor ethnicities of the victims, and the use of DNA profiling technology is the most suitable way to identify the terrorists and keep an end to their violence.