While recent advances in DNA technology have revolutionized the field of forensic science, it also makes us question whether or not the evidence at a crime scene is genuine. Basic techniques such as PCR, molecular cloning, and the most recent whole genome amplification, allow for someone to synthesize DNA under any genetic profile in vitro. This artificial DNA can then be implanted into human tissues or placed on the surface of objects, and planted at a crime scene. Current forensic procedure cannot distinguish between artificial and natural DNA samples.

The company Nucleix is now offering a tool to distinguish between natural and artificial DNA, based on the fact that natural DNA has areas that are consistently methylated. This is when methyl groups attach to areas of the DNA to inhibit gene expression in animal cells. Artificial DNA is completely unmethylated. I wonder how long it will be until someone synthesizes methylated DNA in vitro.