Alternative procedure for DNA recovery from cartridges and casings

Both unfired and fired ammunition recovered from a crime scene are useful in connecting a crime to a specific firearm, however its use in identifying individuals is less common due to low-level or degraded DNA present. Traditionally, the standard procedure for DNA sampling of ammunition evidence is the use of a swabbing technique. The New York State Police (NYSP) Forensic Investigation Center conducted a study to test the efficacy of an alternative method for obtaining DNA from cartridges and casings, soaking the sample prior to extraction. This method presented a 186% increase in total DNA yield, 169% increase in male DNA yield, and a 44% increase in comparable profiles obtained using GlobalFiler(TM) and 240% using Yfiler(R) Plus. Results showed fewer 'no data' determinations using the soaking method, indicating more DNA obtained. Although a statistically significant difference was not observed between the two methods (p = 0.070), a qualitative significance was.