DNA, once considered the most important puzzle piece in solving criminal cases, may not be as foolproof as was once thought, a study revealed.

Israeli scientists at Nucleix Ltd. created the first falsified DNA samples by combining blood and saliva containing genetic code from one person with actual DNA from another to create a whole new set of DNA—something previously thought impossible. Researchers were also able to copy genetic information without using actual tissue by matching a fake sample to a DNA profile in a database.

In an article published in Forensic Science International: Genetics, lead author Dan Frumkin said that with the right resources and financial backing, any person could fake DNA.

“You can just engineer a crime scene,” he said. “Any biology undergraduate could perform this” (New York Times).

The discovery has led some scientists to question the ethical implications for the new discovery, Mr. Frumkin wrote in FSI.

“However, the disturbing possibility that DNA evidence can be faked has been overlooked. It turns out that standard molecular biology techniques such as PCR [polymerase chain reaction], molecular cloning, and recently developed whole genome amplification (WGA), enable anyone with basic equipment and know-how to produce practically unlimited amounts of in vitro synthesized (artificial) DNA with any desired genetic profile. This artificial DNA can then be applied to surfaces of objects or incorporated into genuine human tissues and planted in crime scenes.”

According to Mr. Frumkin, though, the fabricated DNA lacks certain molecules that attach to genetic material at specific spots. Whereas forensic police labs only test for DNA and not the legitimacy of it, he and his team developed an assay that differentiates between a false and real sample.

“This is potentially huge news in the world of criminal justice, which hasn’t yet even fully had the time to embrace DNA for all of its uses,” a CBS News legal analyst said. “And I suspect it won’t be long before defense attorneys are using this study to undercut DNA analysis and conclusions in cases all over the country” (CBS News).

The scientific findings reveal that it may also be possible to use genetic code from a strand of hair or a discarded cigarette to create a saliva sample, which could later be used as evidence to secure a conviction in legal proceedings.