Telling one identical twin from another poses problems for police. And it goes beyond appearances.
That’s because DNA profiling may be the gold standard for bringing criminals to justice, but when it comes to identical twins, standard testing can’t tell the difference.
So when crime scene DNA showed a match to a suspect in two rape cases in Boston in 2004, it showed a match to his twin brother as well.
Now, a Suffolk County prosecutor is trying to persuade a state judge to make her court the first in the country to admit a new forensic test that points to one of the twins — and not the other.
Modern forensic DNA analyses are crucial to crime scene investigations; however the interpretation of the DNA profiles can be complex. Two researchers from the Forensics and National Security Sciences Institute (FNSSI) have turned to computer technology to assist complicated profile interpretation, specifically when it comes to samples containing DNA from multiple people.
Picture the scene. A detective is addressing her team:
“The DNA test results are in. We’re looking for a white male suspect, 34–37 years old, born in the summer in a temperate climate. He’s used cocaine in the past. His mother smoked, but he doesn’t. He drinks heavily, like his Dad. We’re seeing high stress levels, and looking at the air pollution markers, let’s start looking downtown, probably near a major intersection”.
A small British company has clinched a rare deal with the US armed forces, providing them with millions of pounds of kit to test for biological warfare agents. The US Department of Defense has now begun field trials of DNA analysis equipment from Genedrive.
RESTON, Va., Jan. 4, 2017 /PRNewswire/ — With the generous permission of the Rockingham County NC Sheriff’s Office (RCSO), Parabon® NanoLabs (Parabon) announces the company’s participation in the agency’s successful investigation of the murders of Douglas “Troy” and LaDonna French. On 4 February 2012, the Frenches were fatally shot by an intruder in their home in Reidsville, NC. Although DNA evidence was found at the crime scene, it failed to produce a match in any database or among the more than 50 individuals known to have been in or near the French home. In January 2015, nearly three years into the investigation and only a month after the debut of Parabon’s Snapshot Phenotyping Service, RCSO Captain Tammi Howell and Detective Marcus Marshall contacted Parabon about the case. Parabon CEO Steve Armentrout remembers the call: “This was an early case for Snapshot. I recall the investigators’ frustration at having such solid DNA evidence, but no one to match it to. Those are exactly the types of cases for which Snapshot was created.”
SAN DIEGO (CBS 8) – Cold case detectives have the results back from new DNA testing in the 1978 murder of a teenage girl on Torrey Pines beach.
Even though the murder has remained unsolved for 38 years, San Diego police detectives were hoping for a break using wet vacuum DNA collection technology.
WEDNESDAY, Sept. 7, 2016 (HealthDay News) — Certain proteins in the hair can be used alongside DNA in forensics and archeology, researchers report.
DNA is unique to each person but can degrade over time. These hair proteins are more stable than DNA, and can help with human identification, the researchers said.
Imagine you’re a detective working on a murder case. You have a body, but you believe it was moved from another location. Now what? There’s one unexpected tool you might use to follow up on this suspicion: forensic palynology. That’s the application of palynology – the study of pollen – to crime investigation.
Elusive criminals are about to meet their match. Advances in forensic DNA profiling soon will give investigators and analysts the ability to pull genetic data once considered disposable. The breakthrough allows law enforcement to generate information such as gender, hair and eye color, ethnicity and geographic origin from the DNA samples of perpetrators who otherwise might evade detection if they were not part of a DNA database. Gone are the days when non-matching DNA samples signified a dead end.
A Canberra forensic laboratory will be the first in Australia to test the ancestry of crime scene DNA, opening up a world of potentially predicting a suspect’s eye or skin colour.
A DNA evidence bill that would let police in the field, not just technicians in an accredited lab, quickly test the genetic material of suspects has advanced to the House floor.
The measure centers around a relatively new screening instrument the size of a printer, called Rapid DNA.
It’s a staple of the TV-crime drama: a ballistics expert tries to match two bullets using a microscope with a split-screen display. One bullet was recovered from the victim’s body and the other was test-fired from a suspect’s gun. If the striations on the bullets line up—cue the sound of a cell door slamming shut—the bad guy is headed to jail.
Nationwide, about 4,400 unidentified remains are found each year—and more than 1,000 of those are still unidentified a year later, according to the National Institute of Justice, which maintains searchable databases of missing and unidentified persons (NamUs.gov). Medical examiners and local police departments most frequently become the stewards of unidentified remains. And each year, about 20 requests are made to the FBI Laboratory to develop facial approximations of unidentified individuals to help investigators ultimately put a name to a face.
A roadside memorial marks where Sierra Bouzigard’s body was found seven years ago in Calcasieu Parish, Louisiana. There were no witnesses to the murder, and the DNA under her fingernails matched none of the suspects. Yet Detective Les Blanchard—here revisiting the scene—is hopeful a new forensic technique might help solve this cold case.
A new forensic method could allow law enforcement to determine whether blood at a crime scene came from a minor or an adult, and when the suspect or victim left it behind (Anal. Chem. 2016, DOI: 10.1021/acs.analchem.6b01169).