Police may now unravel the strands from samples containing more than a single DNA by a new crime tool developed in New Zealand.
The software, called STRmix, has been sold to the US Army, and the FBI is already in talks to acquire it.
Institute of Environmental Science and Research scientists John Buckleton and Jo-Anne Bright, collaborated with Duncan Taylor from Forensic Science South Australia, created STRmix using standard maths and "Monte Carlo processes" - sampling thousands of different possibilities and using chance "many, many times", Stuff.co.nz reported.
The software was put into work in August 2012, and has been used in several prosecutions.
The tool takes seconds for simple cases, and up to days for complex cases. It currently is able to separate four strands.