When police technicians investigate a crime scene, they look for DNA tracks, among other things. They are found in food residues, clothing and in various body fluids such as blood and semen. DNA analysis can bind a suspected criminal to the scene and is important evidence.

Better analysis

Some of these samples are dirty and cannot be used. Proteins found in the blood and substances found in soil can cause too few cells to detect a DNA hit.

But new research done in collaboration between Lund University of Technology and the National Forensic Center in Linköping has found alternative methods of analysis that now allow samples that were previously considered dirty. The results have been presented in a thesis written by Maja Sidstedt in Linköping. Research has already led to improved DNA analyzes being done.