One cell is enough for forensic DNA fingerprinting

A new technique for fingerprinting DNA from a single cell may have tremendous potential for forensic investigations and other applications, allowing individuals to be identified from just one cell. Developed by Dr Ian Findlay, a senior research fellow at the Australian Genome Research Facility (AGRF) in Brisbane, the method is a highly refined version of the standard DNA fingerprinting technique used increasingly by forensic scientists.

But while the standard method needs at least 200-500 cells in order to produce validated results, Findlay's technique can do it with one. It uses a selection of the 25 or so DNA markers commonly used for fingerprinting, with conditions optimised for a single cell's worth of DNA. And the method has potential for high throughput analysis, allowing several thousand to be processed a day.

Single cells could be isolated from a variety of materials, according to Findlay.

"We've certainly demonstrated that we can get single cells from paper," he said. Other potential sources of cells include glass, plastic and clothing.

However Findlay said that while the forensic community was cautiously excited about the new technique, more work was required to validate the approach before it was suitable for regular use by forensic labs.

"There are serious implications if we get this wrong," he said, noting that the current methods had been thoroughly validated prior to becoming standard forensic techniques.

According to Findlay, he first started working on the technique as a method of testing for genetic abnormalities in embryos.

"We developed a single cell fingerprinting system for this, then realised that there would be hundreds of other applications," he said.

Among those applications are the use of the technique for document security purposes, to track the flow of documents.

On the medical and research side, the technique might allow single cell biopsies, and gene expression and manipulation experiments in single cells.

"We've really just scratched the surface," Findlay said. He is currently concentrating on the two original applications, prenatal diagnostics and forensic DNA fingerprinting.

Findlay is also thinking about the best way to commercialise the technology. Patent protection has already been applied for, he said, and they are investigating potential commercial partners and funding sources to take the technology to a commercial level.

"We're still thinking about the best way to do this," Findlay explained.