Monthly Archives: September 2012

It isn't pretty, but it's a first for science. A dead body, burned beyond recognition, was discovered in the woods by Mexican police. Investigators had a lead on the identity of the victim, but the body was too damaged to provide DNA for analysis. That is, until scientists stepped in with an innovative and unorthodox solution: extracting DNA from maggots found on the corpse.

Pathologists from the Autonomous University of Nuevo Leon, in San Nicolas, Mexico, dissected three maggot larvae found on the corpse and extracted the contents of their gastrointestinal tracts. They were then able to isolate the human DNA found within and find a match.

Police believed the victim to be a young woman who had been reported missing ten weeks earlier. The DNA from the maggots was compared to samples taken from the woman's father and found to be a 99.68 percent match.

The pathology team, led by Maria de Lourdes Chavez-Briones and Marta Ortega-Martinez, reported their work in the Journal of Forensic Science. The idea of extracting human DNA from insects has been studied for several years. But this was the first time the theory was put to practice in a criminal case.

The team hopes that their work will encourage law enforcement officials to pay more mind to insects found at crime scenes.

Read more:
Burn victim identified by DNA in maggots

NEW ORLEANS

Damon Thibodeaux received the ovation you'd expect of a man who's just been exonerated of a crime he didn't commit.

WGNO News Reporter Darian Trotter asked, "How do you feel now? Free, Thibodeaux replied."

Damon Thibodeaux has been on death row in Louisiana since October, 1997.

He was convicted of the murder and rape of his 14-year old step-cousin, Crystal Champagne.

It was a crime for which he had been coerced into falsely confessing.

But DNA and other evidence have proven his innocence.

It took seven years and hundreds of thousands of dollars of DNA testing for the Innocence Project and Jefferson Parish prosecutors to exonerate Thibodeaux.

"When you think you have an innocent man and people on both sides can get together and really share evidence and conduct an investigation into the search for the truth that's what's important. So we are tremendously indebted to Paul Connick and his team for the cooperation and the integrity with which they went about this process," Innocence Project Co-Director Barry Scheck said.

Thibodeaux makes the 300th person to be exonerated by DNA evidence in the U.S. And the 18th who served time on death row.

Link:
DNA Clears Death Row Inmate

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IRA FLATOW, HOST:

This is SCIENCE FRIDAY, I'm Ira Flatow. We're here in Boise, Idaho, talking, broadcasting from the campus of Boise State University, and we're going to talk about the use and abuse of DNA evidence, excuse me. Forensic techniques to investigate crime scenes have been coming under increasing scrutiny.

Questions have been raised about fingerprint interpretation, blood-spatter analysis, bite-mark and fiber analysis, but DNA, DNA has been held up as a gold standard in forensics. DNA found at the crime scene matches the suspects? Case closed most of the time.

But my first guest says we should be taking a closer look at how we use DNA. Not all DNA evidence is created equal. Sampling techniques are changing, so the standards for using DNA evidence should be changing, too, he says.

Greg Hampikian is director of the Idaho Innocence Project and a professor in the Department of Biological Sciences and Criminal Justice here at Boise State University. Welcome to the program.

GREG HAMPIKIAN: Thanks very much.

FLATOW: Walk us how through DNA evidence is collected at the scene of a crime.

HAMPIKIAN: Well, that's changing, but, you know, in a lot of our rural communities, it hasn't changed much at all in 20 years, probably. So you don't always have a CSI team and booties and...

FLATOW: It's not like on television, in other words.

View post:
Analysing The Evidence On DNA

VANCOUVER - RCMP scientists will continue to resubmit DNA to Interpol after announcing this week the process confirmed a dead U.S. convict killed at least one of the 18 victims on B.C.'s so-called Highway of Tears, an investigator said Thursday.

Staff Sgt. Wayne Clary said samples of genetic material submitted to the international law enforcement agency have to meet standards, which could mean having to isolate the suspects DNA from other contaminants, including blood from the victim.

That was the case in victim Colleen MacMillens murder: her blood was mixed with that of her presumed killer, Bobby Jack Fowler. (Fowlers guilt is not proven in a court of law because of his passing in 2006 in an Oregon prison.)

A previous attempt five years ago to separate Fowlers blood was unsuccessful, but new technology made it possible this year. That meant the isolated Fowler DNA was now acceptable for comparison with international police records.

Were very cognizant of advances in DNA and we would resubmit when we can, Clary told QMI Agency. In particular, when there are older cases that have already gone through (our system) once.

The investigator said police have also traced four additional British Columbian male suspects -- two living and two dead -- related to the missing and murdered women.

One of the suspects continues to be sought in connection to Maureen Mosies death. The 33-year-old was last seen alive in Salmon Arm on May 8, 1981. The next day, her remains were located 100 kilometres west, near Kamloops.

Mounties still seek witnesses who saw a two-door compact car with an Alberta plate driven by a man with a dark beard.

We think whoever drove that car killed Maureen Mosie.

Though no names were released, Clary said the two dead suspects linked to two separate killings perished before the Highway of Tears task force launched in 2005.

Continued here:
DNA remains focus in Highway of Tears cases