Forensics

We recently introduced DNAWitness™2.5 to the forensics market. Law enforcement officers use this testing service to determine genetic heritage from DNA samples obtained from crime scenes, narrowing the potential suspect pool to a more focused group of likely candidates. The test enables law enforcement agencies to reduce both the cost and time needed to apprehend suspects. Current forensic DNA products in the market act like a fingerprint and can only be used to match DNA specimens. DNAPrint® is the first forensic product that provides predictive capability. DNAWitness™ will provide the percentage of genetic make up amongst the four possible groups of Sub-Saharan African, Native American, East Asian, and European. When appropriate, DNAWitness™ allows for a breakdown of the European ancestry into four components: Northwestern European, Southeastern European, Middle Eastern and South Asian.  The names of the components/groups is meaningful but not exact, since they are cast in modern-day terminology but the assay is an anthropological one that reports affiliation with populations who share common ancestry extending back many thousands of years.  The real value of the percentages reported are as population (rather than individual) bar-codes, which are very useful for inferring certain elements of physical appearance. 

Initial DNAWitness™ 2.5 customers include medical examiner's offices, special task forces, sheriffs' departments, and district attorney's offices from various cities. These cities include the three largest U.S. metropolitan areas of New York City, Los Angeles, and Chicago.

Initial response from preliminary application of this forensics version to various high profile criminal cases has been promising.   

Derrick Todd Lee, the alleged Louisiana serial killer, was recently apprehended and has been convicted for first-degree murder and aggravated rape. The Louisiana Multi-Agency Homicide Task Force (including the Baton Rouge Police, the FBI and other agencies) had initially relied on faulty eye-witness testimony to develop a “Caucasian” description for the “person of interest”.  DNAPrint® was hired to analyze the DNA evidence left at some of the crime scenes and determined that the suspect was 85% Sub-Saharan African and 15% Native American. Based upon these findings, the Task Force materially altered the focus of their investigation and included Derrick Todd Lee as a person of interest. ABC’s Prime Time Thursday recently featured DNAPrint® with a story detailing the role DNAWitness™ had in the resolution of this case. In addition, this case was featured in US News and World Report (June 23, 2003), the New York Times (June 3, 2003), Popular Science (December, 2003), and prior to the case, by CBS Evening News.

We have performed about 13,000 “blind” tests to date.  For example, one west coast police department sent 16 samples collected from members of the department. The results were judged by them to be correct (consistent with phenotype and self-held notions of ancestry) for all 16 samples. Similarly, an east coast police department sent 20 blind samples and DNAPrint® accurately predicted the genetic heritage of all 20 people.

We introduced an expansion of DNAWitness™ 2.5 by bringing out EUROWitness™ 1.0 which breaks down the four major groupings of Sub Saharan African, Native American, East Asian and Indo-European provided a DNAWitness™ 2.5 test comes back with 50% or greater Indo-European, it is eligible for EUROWitness 1.0 that further refines the admixture to Northwest European, Southeastern European, Middle Eastern and South Asian.

We also in 2005 released our RETINOME™ assay. RETINOME™ provides a dramatic improvement in our ability to construct a physical portrait of a person of interest for a detective based on a DNA sample from a crime scene or remains of an individual.  RETINOME™ allows us to infer eye (iris) color from DNA and this SNP based method for testing eye color is the first of its kind. The method employs proprietary computational methods and combines human pigmentation gene SNP combinations and ancestry informative markers to predict human eye color directly, accurately and sensitively. Validation experiments necessary to define the precise accuracy reveal that the inferences are correct about 92% of the time – performance that is quite respectable given the genetic complexity of iris coloration. We continue to work on hair color, skin pigmentation and other physical characteristics that scientists have or have not yet identified gene markers.

DNAPrint®’s portfolio of services will now include an array of presumptive tests that will help detectives tackle the nearly 1.2 million reported incidents of violent crime in the U.S. Statistics from the National Institutes of Justice and many local and state agencies generally report that only about 50% result in an arrest, and only a small percentage of those result in a criminal conviction. In violent crimes, DNA evidence is left at a crime scene or on a victim’s body in the vast majority of cases. Most investigators highly value physical descriptions of individuals or persons of interest obtained from human eye-witnesses.  However, as the Louisiana case illustrates, eye-witnesses can be mistaken, and sometimes they are subjective, inaccurate or sometimes intentionally misleading, generally however most eye witnesses try to accurately report what they have seen. Unfortunately, sometimes several people at a crime scene will report conflicting descriptions. Detectives can corroborate eyewitness reports or perhaps even change the direction of an investigation despite eyewitness reports based on our analysis of the DNA.

DNAWitness™ provides a “molecular” eye-witness that is more scientific because it is a quantitative analysis of inherited genetic markers.  Moreover, DNA is more readily available from most crime scenes.  As we continue our research, we intend to develop additional assays that address other inherited traits that bear on physical appearance.  The idea is to provide a drivers license for each person of interest from a crime scene analysis, with as many of the physical descriptors as possible (minus their name and address of course).

Hundreds of thousands of rape-kits sit on shelves of investigative agencies around the country.  For how many of them would accurate physical descriptions be useful in a more timely apprehension?  In addition, there is a recent trend in the legal system to retroactively test DNA evidence left at crime scenes to substantiate or invalidate the previous legal defenses of incarcerated individuals. DNAPrint®'s technology could be used to screen the DNA samples and categorize them. For example, if the results of DNAPrint®'s testing shows that the DNA from the crime scene belongs to a an European individual and the incarcerated individual is an African American, that DNA would have priority for the more laborious and time-consuming STR testing because the likelihood of vindication is high. In recent years there have been more than 130 exonerations of previously convicted individuals based on DNA evidence. With the use of DNAPrint®'s DNAWitness™ 2.5, the length of wrongful incarceration for innocent individuals could be shortened. 

Forensics