Methods enhancement for improved recovery of human DNA from forensic blood samples on different fabrics using the DNA IQ System

Abstract

DNA typing of biological samples can be a challenging task due to the presence of small amounts of DNA and/or a high content of PCR inhibitors. Our aim is to develop a protocol to recover DNA suitable for DNA typing from blood-stained fabrics based on the DNA IQ System. Blood stains on different fabrics were buried in different types of soil and left for 1–7 days. The samples were then recovered and DNA was extracted with a modified DNA IQ System protocol, involving a modification in the preparation of the Wash Buffer. The samples extracted with the modified protocol showed a higher amount of recovered DNA compared with the recommended protocol. The removal of isopropanol from the Wash Buffer composition contributes to a higher amount of recovered DNA.

Keywords:

• degraded DNA
• DNA extraction
• DNA IQ system
• low amount DNA