George Zimmerman trial: Trayvon Martin's DNA not on Zimmerman's gun, DNA analyst testifies

George Zimmerman, left, arrives in Seminole circuit court, with his wife Shellie, on the 11th day of his trial, in Sanford, Fla., Monday, June 24, 2013. Zimmerman is accused in the fatal shooting of Trayvon Martin. Zimmerman has been charged with second-degree murder for the 2012 shooting death of Trayvon Martin. (AP Photo/Orlando Sentinel, Joe Burbank, Pool)
Joe Burbank
Florida Department of Law Enforcement Crime Lab Analyst Anthony Gorgone points to a jacket worn by George Zimmerman on the night Zimmerman shot Trayvon Martin during the George Zimmerman trial in Seminole circuit court, July 3, 2013 in Sanford, Florida.
Photo by Jacob Langston-Pool/Getty Images

(CBS) -- Slain Florida teen Trayvon Martin's DNA wasn't detected on George Zimmerman's gun, a Florida Department of Law Enforcement DNA analyst testified Wednesday.

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Anthony Gorgone also testified that George Zimmerman's DNA wasn't found under the teen's fingernails.

Zimmerman, a former neighborhood watch captain charged in Martin's shooting death, claims he killed the teen in self-defense during an altercation last year in a Sanford, Fla. gated community. Zimmerman said Martin slammed his head into a sidewalk and reached for his gun before he fatally shot the teen. He is charged with second-degree murder.

In court Wednesday, attorneys displayed items of clothing Zimmerman and Martin were wearing the night of the fatal altercation that Gorgone tested for DNA, including Martin's hoodie and Zimmerman's red jacket.

Gorgone said he didn't detect any DNA that wasn't Martin's on the cuffs and sleeves of Martin's hoodie. 

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Responding to questions from defense attorney Don West on cross-examination, Gorgone said it was possible to touch something without leaving DNA evidence.

"Sometimes you can touch an item and there won't be any DNA," West said. "Sometimes there can also be blood, but it can be wiped off."

"That's correct," Gorgone said.

On cross-examination, Gorgone told West that he detected an odor when he removed Martin's hoodie from the plastic bag it had been packaged in, likely because it had been packaged wet. 

It was raining the evening of the fatal struggle. "It had a very pungent odor," Gorgone said.

Ideally, he said, clothing should be air-dried and packaged in paper bags, not in plastic as Martin's hoodie had been.

West asked whether the plastic packaging could place "biological evidence at risk of degradation."

"That's correct," Gorgone said.

Court will recess for the Fourth of July holiday Thursday and re-convene on Friday. Prosecutor Bernie de la Rionda said in court Wednesday that the state will rest their case by "Friday morning at the latest."

  • Erin Donaghue

    Erin Donaghue covers crime for's Crimesider.