THE GENETIC profiles held by police for criminal investigations are not sophisticated enough to prevent false identifications, according to the father of DNA fingerprinting.
Professor Sir Alec Jeffreys, a geneticist at Leicester University, England, said police DNA databases should hold more information to lessen the chances of a false positive.
Genetic profiles stored by the Police normally record the details of 10 specific parts of the long chain of molecules that make up a personâ€™s DNA. The chances of two unrelated people having the same details for all these 10 markers â€” and hence the chance of a false identification â€” is said to be about one in a billion. This method has traditionally been regarded as highly efficient at identifying suspects from DNA traces left at crime scenes.
However, Prof Jeffreys said the increasing number of records being held on the UK police database meant that having only 10 markers per person was no longer foolproof.
He suggested 15 or 16 markers to reduce the chances of two people having the same profile. American law-enforcement authorities are already considering changing the profiles in their DNA databases along these lines.
In Britain, DNA evidence has been used in countless criminal investigations and the police regard it as an invaluable tool.
DNA fingerprints â€˜not foolproofâ€™