Powerplex® ES versus Powerplex® S5--casework testing of the new screening kit

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• Forensic DNA analysis often encounters degraded DNA from casework samples.
• Existing kits may yield poor results with highly degraded or inhibitor-containing DNA.

Purpose of the Study:

• To evaluate the Powerplex® S5 Mini STR-System as a screening tool for difficult forensic casework samples.
• To compare its performance against the Powerplex® ES kit for degraded DNA analysis.

Main Methods:

• Amplification of highly degraded DNA from casework samples and artificially degraded DNA.
• Inclusion of DNA samples with PCR inhibitors.
• Comparison of results with the Powerplex® ES kit.

Main Results:

• The Powerplex® S5 kit demonstrated reliability in analyzing degraded DNA, yielding better results than the Powerplex® ES kit in 64% of analyzed swabs.
• Allelic drop-in was observed in highly degraded DNA amplification.
• The system proved effective for formalin-fixed tissues, putrefied samples, and telogen hair.

Conclusions:

• The Powerplex® S5 Mini STR-System is a valuable screening tool for challenging forensic casework samples with degraded DNA.
• It offers improved performance over the Powerplex® ES kit for certain sample types.
• No direct correlation was found between positive Powerplex® S5 results and Powerplex® ES kit amplification success.