Forensics reaches into the future
How far should we let the DNA database go?
Familial searching may indeed be one technology which will help satisfy Blair's ambitions for an all-encompassing DNA repository. It means that if authorities turn up a DNA profile from a crime scene and run it on the database, it's not a wasted enterprise if they don't turn up an exact match. Though our DNA fingerprint is effectively unique, it shares similarities with blood relatives'.
The FSS added familial searches to its armoury this year, along with DNAboost, a less controversial procedure which gives forensic scientists stronger tools at the other end of the DNA profile: the crime scene. Rather than an insufficiently enormous database, difficulty getting good samples from a crime scene is often the reason forensics draw a blank. DNA may be mixed from several individuals or have degraded over time.
DNAboost is a computer program the FSS developed inhouse which turns the problem of poor sample on its head. FSS consultant forensic scientist Dr Tim Clayton, who works with DNAboost, told us the lateral thinking at its foundation is "beautifully simple, like all the best ideas".
It works by turning the database search into a process of elimination, so rather than looking for a match, it compares the sample's DNA fingerprint to every entry in the NDNAD and ranks them for similarity. A lot of the time it ends up finding the person they're looking for, and we learned that there are already several active prosecutions which used DNAboost as part of the investigation.
It's not an evidence-building tool then, but an investigatory one, and so part of the mission creep which Alec Jeffreys fears. At the EPSRC event in March it was clear that that is the future of forensics technologies, however.
Improvements in current techniques are perhaps the best hope civil libertarians have to stymie further expansion of the NDNAD. So-called "lab-on-a-chip" analysis looks set to revolutionise collection and testing of crime scene samples. The "chips" at the centre of the putative devices are not silicon microchips, rather pieces of plastic an inch or so across with drilled capillaries. The chemicals needed for DNA analysis can be controlled using the capillary design, putting the power of DNA analysis in the hands of scene of crime officers.
The field is moving rapidly, and the research councils are keen to fund projects as the designs migrate from academic research into working prototypes. The EPSRC gave £721,000 to lab-on-a-chip efforts at the University of Hull, which expects to begin field trials of a device within two years. Their machine will aim to detect and separate out DNA ready for fingerprinting in double quick time.
The final frontier
Without more oversight, few people we spoke to see an end to the NDNAD's mission creep. It is only a matter of time before DNA sequencing is both fast and cheap enough for entire genomes to be mapped to order.
TheX Prize Foundation, which drove the race for the first commercial space flight, has already laid down the gauntlet by offering $10m for the first team to sequence 100 genomes in 10 days. The billionaires reckon the achievement will herald a new era of personalised medicine and exotic targeted therapies.
The argument for whole genome forensics is sure to follow. Cast-iron evidence will be the call; cases have been lost because of the small chance of a false positive match with DNA fingerprinting. The Home Office hangs on to DNA samples once it has fingerprinted them already, so anyone who develops the technology to sequence them could have a fat government contract awaiting them too - 3 million-plus samples await. ®