More for the same? Enhancing the investigative potential of forensic DNA databases (REF 0415)

The UK has had a National DNA Database [NDNAD] since 1995. It now contains more than 4.5 million records representing 7.5% of the UK population. The Forensic Science Service has introduced two additional services designed to supplement and enhance the ability of law enforcement agencies to investigate offences. Both employ novel and bespoke software that exploit data held on the NDNAD to greater effect than using direct matching algorithms. The first service, 'familial DNA searching' [fDNA] was introduced in 2003 and has now been applied in over one hundred serious offences. In these cases, although a crime DNA profile was in existence, the offender's profile was not present on the NDNAD; instead the focus is to search for a potential relative of the offender. A number of successful detections have been obtained and the data generated from those operations have been collated and studied. We present an overview of the data and discuss a number of refinements which have been implemented from the experience gained. The second and most recent service to be introduced employs proprietary software called DNAboost(r) and applies it to complex DNA mixtures which cannot be resolved to allow for a standard search. A mixed DNA profile is 'de-convoluted' to generate all feasible DNA profiles in order to interrogate a DNA database of named individuals. The paper will discuss how this has been achieved and the initial results of the operational testing of the software.