By Ben Butkus
This article was originally posted on March 16.
Hamilton Robotics and the Institut National de la Police Scientifique in Lyon, France, have published a peer-reviewed paper describing how Hamilton's automated liquid-handling workstation has been used to help prepare profiles for France's national genetic reference database.
The paper describes one of the first examples of large-scale automation of forensic DNA processing and analysis, and the company is hoping that other forensic labs worldwide will adopt Hamilton's platform to aid in genetic database creation, company officials said this week.
Hamilton's automated liquid-handling workstation, the Microlab Star Plus, has been commercially available since 2001, and the company has sold approximately 3,000 units since that time, Jörg Katzenberger, marketing communications manager, and Laurent Baron, forensics product manager at Hamilton, told PCR Insider.
The platform is used primarily in academic labs for basic research and in pharma companies for high-throughput assays and sample setup, including for applications such as PCR and nucleic acid sample preparation, Katzenberger said.
In 2004, Reno, Nevada-based Hamilton, which also maintains facilities in Bonaduz, Switzerland, collaborated with the Institut National de la Police Scientifique, or INPS.
The goal of the collaboration was to automate the production of France's reference sample database, which includes genetic profiles from DNA samples collected from all individuals processed by INPS in relation to a crime.
Like many forensic labs worldwide, genetic profiles are amplified from bucal swab cells, blood, or some other biological material collected on FTA cards, which are manufactured by Whatman, a GE Healthcare company.
FTA cards contain chemicals that lyse cells, denature proteins, and protect nucleic acids from nucleases, oxidative, and UV damage; and DNA collected on FTA cards is stable for years at room temperature, according to Whatman's website.
As such, INPS – like many forensic labs – had a backlog of thousands of DNA samples collected on FTA cards that needed to be amplified via PCR for entry into the central database – and was constantly collecting more samples.
Forensic labs have traditionally performed this task manually – "but when the number of samples gets into the thousands it gets quite tedious," Katzenberger said.
As described in a special genetics supplement to the December 2009 issue of Forensic Science International, Hamilton and INPS developed a protocol for the Microlab Star Plus that automatically processes samples both before and after PCR.
The process entails punching samples from FTA cards using automated punchers from BSD Robotics, into 96-well PCR plates from Bio-Rad. The system then automatically moves the plates through centrifugation and washing steps; transfers them to a temperature-controlled carrier; and adds STR Identifier PCR mastermix from Life Technologies' Applied Biosystems business.
Thermal cycling can be performed on any appropriate PCR instrument, after which the system automatically performs centrifugation and sample denaturation, completing the process. The entire process is controlled using Hamilton's Venus One software; samples are tracked throughout the process and data is transferred to a laboratory information management system.
Since the system's installation in September 2006, more than 300,000 genotypes have been processed in duplicate on the pre- and post-PCR systems and entered into the French National Fingerprint Database, according to the paper.
Initially the system's throughput was set to process 20,000 samples per month, but in December 2008 it was increased to 40,000 samples per month without any major hardware modification, the paper states.
According to Hamilton's Baron, INPS' biology section is now using the system to analyze about 30,000 casework samples per year, while INPS' central DNA database laboratory has been using the system with a production capacity of about 40,000 genotype analyses per month.
"When the platforms were installed in Lyon and up to now, very few labs have fully automated the FTA process with such throughput," Baron said. "FTA is a very efficient and simple way of collecting, storing, and shipping samples. This technique is more and more widely used. Originally cotton swabs were more widely used to gather samples for databases but automation is difficult and the genotyping process requires DNA extraction and quantification steps, which make the process longer and sample processing costs higher."
Another benefit to using the automated FTA card processing system is the ability to more accurately track samples, Katzenberger said. "If you have to manually put punches from cards in each well of a 96-well plate, how do you make sure the punch has entered the correct well?" he said. "It is very difficult. This aspect is probably even more important than the throughput."
Katzenberger also noted that there are "very few examples, if any, of automation of this process," but added that Tecan is one of Hamilton's main competitors in this area.
He said that Hamilton believes the paper, which was submitted for peer review at the behest of INPS, will drum up interest in using the Microlab Star Plus in other forensic labs worldwide that are building genetic databases.
"It's a very sensitive area," Katsenberger said. "You certainly don't want to be entered into this database." As such, there is a market in the US and parts of Europe that is open but somewhat limited. But the company is also eyeing markets in countries where there are fewer privacy and consent concerns, particularly in some Eastern European countries and China.