NDIS DNA Profiles Include More Data in 2017

With the start of the new year, forensic labs across the country are realizing a big change in the way they generate DNA profiles, the genetic fingerprints so useful in solving crimes and identifying the remains of missing persons. Forensic experts produce DNA profiles by extracting genetic material from blood or other biological evidence and analyzing sites in the DNA called markers.

Since the FBI’s National DNA Index System, or NDIS, came online in 1998, forensic labs in the United States have been generating profiles by analyzing a specific set of 13 genetic markers.

Starting January 1, 2017, that number rose to 20, an advance made possible by close collaboration between scientists at the FBI and the National Institute of Standards and Technology (NIST). The additional markers vastly increase the statistical certainty of DNA identifications and allow investigators to identify suspects that could otherwise slip through the cracks.

To meet the new year’s deadline, all labs that submit profiles to NDIS had to upgrade their protocols and meet a series of quality assurance standards set by the FBI.
This upgrade was necessary in part due to the rapid growth of the system, which has expanded to include nearly 16 million profiles related to criminal investigations and 30,000 related to missing persons. NDIS now has to add more markers for the same reason a growing city might have to add a new area code. It ensures that everyone can have their own number.

In addition, this upgrade makes international DNA searches more effective by increasing the number of markers that the U.S. system has in common with those of other nations. The number of markers used in both the United States and Europe, for example, will rise from eight to 15.

The new markers will also help solve a problem that often comes up in cases where the DNA has started to break down. In those cases, forensic analysts can’t always get a read on all 13 markers, and they end up with a partial profile.

“If you’ve got a case where seven markers drop out, the statistics may be too weak to establish an identity,” said Mike Coble, a research geneticist at NIST. When that happens, a perpetrator might escape the notice of investigators and remain free to commit more crimes.

“But if you start with 20 markers, seven can drop out and you’ll still have what’s considered a full profile today,” Coble said.

Of the seven new NDIS markers, three were first identified by Coble and his colleagues at NIST. And those three markers were chosen because they are particularly useful in cases where the DNA has started to break down.

You can

read more about the update here.

 

 
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