An investigation of two methods of DNA recovery from fired and unfired 9 mm ammunition

Recent advances in forensic biology and forensic DNA typing: INTERPOL review 2019–2022

“…Research studies and review articles have considered factors affecting DNA recovery from cartridge cases and the impact of metal surfaces on DNA recovery [ [202] , [203] , [204] , [205] , [206] , [207] , [208] , [209] ]. Recovery of mtDNA from unfired ammunition components has been assessed for sequence quality [ 210 ].…”

Recovery of DNA from fired and unfired cartridge casings: comparison of two DNA collection methods

“…Of the ten cartridges, only two samples produced STR profiles with one allele each. They concluded that ammunition obtained from a manufacturing facility was primarily DNA free [23]. In addition, Montpetit & O'Donnell [1] reported that the manufacturing process is largely automated with few human quality assurance checks (less than 1% of manufactured ammunition), for ammunition from Federal Ammunition (Anoka, MN).…”

“…Additionally, [1] and Moore et al [23] noted that less DNA quantity was obtained from fired casings than from unfired cartridges. Of the 583 samples suitable for STR analysis, 290 were fired casings and 293 were unfired cartridges.…”

“…Samples have been concentrated using Microcon Centrifugal Filters to increase the odds of developing full profiles. Semi-automatable direct lysis methods using liquid handlers, like the Hamilton MicroLab STAR AutoLys robot have shown significant increases in DNA recovery compared to double swab methods by reducing the number of steps requiring human interaction [23]. The addition of 0.5 M ethylenediaminetetraacetic acid (EDTA) to a cotton swab has been found to reduce the effects of copper ions in the extract as EDTA is known to chelate metal ions in solution, reducing the likelihood of copper ion coextraction [24].…”