DNA reviews: low level DNA profiling.

Low copy number (LCN) DNA profiling has recently been scrutinized in the United Kingdom following the comments of Mr Justice Weir made during the trial of suspected terrorist Sean Hoey. Mr Hoey was acquitted of all charges related to the Omagh bombing of 1998, following the inadmissibility of key DNA evidence during this trial. The Association of Chief Police Officers and Crown Prosecution Service, initially suspended the use of this technique, but quickly reinstated its use following an internal enquiry. This review describes the low copy number technique and the sample types that are now routinely collected from suspects, victims, and crime scenes for examination by this method.