Pennsylvania prosecutors use TrueAllele in homicide guilty plea

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Solving cold cases by TrueAllele® analysis of DNA evidence

M.W. Perlin, "Solving cold cases by TrueAllele® analysis of DNA evidence", Finding Closure: The Science, Law and Politics of Cold Case Investigations, Cyril H. Wecht Institute of Forensic Science and Law 14th Annual Symposium, Pittsburgh, PA, 31-Oct-2014.


PowerPoint presentation with live audio recording of Dr. Perlin's talk.

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DNA databases are a powerful investigative tool for solving cold cases. But 20th century DNA interpretation and databases cannot separate mixtures into component genotypes, so are often unhelpful. TrueAllele® Casework is a 21st century method that reliably separates DNA mixtures into genotypes, and produces accurate match statistics.

A British rape case illustrates how TrueAllele works with multiple hits from DNA databases. The talk also describes how a TrueAllele database can help prevent rape on college campuses, in prison and in the military. More sophisticated use of DNA information can help build a safer society.


Unlike TrueAllele, some STR mixture analysis methods discard peak data below a certain "threshold" height. The study by Kloosterman set a 10 rfu threshold (baseline noise) for TrueAllele, and a 50 rfu threshold for the other methods. Using a threshold, or adjusting its level, can significantly change the match statistic, as mentioned in the talk.