Reduction of PCR-amplifiable DNA by Ethylene Oxide Treatment of Forensic Consumables

• NCJ Number: 248158
• Journal: Forensic Science International Genetics Volume: 12 Dated: September 2014 Pages: 185-191
• Author(s): Katharina Neureuther; Edyta Rohmann; Manuela Hilken; Marie-Luise Sonntag; Silke Herdt; Thomas Koennecke; Ronald Jacobs; Michalina Adamski; Stefan Reisbacher; Knut Alfs; Peter Strain; Ingo Bastisch
• Date Published: September 2014
• Length: 7 pages
• Publication Format: Article
• Publication Type: Research (Applied/Empirical); Report (Study/Research)
• Language: English
• Country: Ireland

Annotation

Although previous published studies have shown ethylene oxide (EO) treatment to be an effective method for rendering molecular biology products free of contaminating DNA, the current study conducted additional experiments under conditions more reflective of forensic practice.

Abstract

The study confirmed the finding of earlier studies in showing that chemical EO treatment is more successful in reducing the amount of PCR amplifiable DNA than ionizing radiation. In addition, this study found that the efficacy of EO treatment is affected by the nature of the samples; i.e., DNA in saliva was more susceptible to damage by EO gas than DNA in blood, and the accessibility to EO gas had a strong influence on the method's efficiency. Although the treatment of samples in cotton swabs packed into gas permeable bags was successful, samples inside a closed micro test tube were resistant to the same treatment conditions. The work with defined K562 cell numbers and multi-copy quantitative PCR could show that a 5-hour EO treatment results in a reduction of PCR-amplifiable DNA. Corresponding STR-PCR results also show only sporadic allele calls in the mini-loci range. This provides a reliable interpretation of forensic analysis. The authors recommend an EO treatment of forensic consumables and a multi-copy quantitative PCR approach in establishing reliable treatment conditions. 2 figures, 2 tables, and 16 references