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Dateline extra – Hear more from DNA expert Dr. Mark Perlin
New York, NY
On Friday, Dateline aired a two-hour NBC news episode on the brutal 2006 slaying of Blairsville dentist Dr. John Yelenic by former Pennsylvania state trooper Kevin Foley. DNA evidence under the victim's fingernails pointed to Foley.
In a two-minute extra, Dateline correspondent Andrea Canning interviewed Dr. Mark Perlin, the Cybergenetics scientist who testified at the Foley trial about the true DNA match results.
Canning noted Perlin "developed a new way to analyze DNA." She asked him, "What did you develop?" Perlin talked about the TrueAllele® supercomputer that finds all the DNA information, and doesn't "simplify the data" like limited human methods.
In the Foley case, the FBI's old way of examining DNA mixtures gave a very low match statistic for Yelenic's fingernails. But Cybergenetics' TrueAllele® computer found a more accurate match value.
Canning said, "The FBI had found the chances of this being Kevin Foley were about 1 in 13,000 that it was his DNA." She asked Perlin, "What did your test reveal?"
Dr. Perlin replied, "TrueAllele used exactly the same data, and was able to get more information, and ended up with a number of 189 billion from the same evidence."
Foley's 2009 trial was the first time such advanced DNA mixture interpretation was ever heard in a courtroom. The pioneering TrueAllele science is now widely used.
Dateline's Canning asked Perlin, "How satisfying is it that your method went on to become the gold standard for DNA testing?"
"I think we are more gratified that it is having an impact on criminal justice," he answered. "When you know that someone has been in jail for 25 years - and the only reason he is out of jail, and has been exonerated, is your technology."
- Hear more from DNA expert Dr. Mark Perlin - Dateline
- NBC Dateline presents the first TrueAllele case - Cybergenetics
- Dentist’s gruesome murder baffled police, but led to breakthrough in DNA technology - Oxygen
- The DNA story of the Yelenic murder trial – Book chapter (2013)
- Decades of forensic failure with DNA mixtures – Magazine article (2018)
- TrueAllele computer analysis of Yelenic’s DNA fingernail evidence – PLoS ONE (2009)
- When people can interpret DNA mixtures, computers do better – Journal of Forensic Sciences (2011)
- When computers interpret DNA mixtures, people usually cannot – Journal of Forensic Sciences (2013)
- Human analysis of Yelenic fingernail DNA was just random counting – Journal of Pathology Informatics (2015)