LCN DNA Analysis

LCN DNA was developed by the UK Forensic Science Service (FSS) in 1999. The technique, performed by only a few laboratories across the world, is extremely expensive but is necessary when only small amounts of DNA are recovered for analysis.

Low Copy Number (LCN) DNA analysis is like traditional DNA analysis. The purpose is the same: to try and match the DNA extracted from cells found at the scene of the crime.

The upside of this type of DNA profiling is that it allows a very small amount of DNA to be analyzed, even the DNA from just 15 to 20 cells.

Forensic investigators are able to target areas on items where it is believed that an offender may have transferred DNA through touch, like the residue from cells such as skin or sweat, left in a fingerprint

Because of the small amount of starting DNA, many more cycles of replication are necessary and contaminants will be also be replicated, creating a greater risk of inaccurate results.

A correct fingerprint identification on a fixed object, may establish that you were at a particular point, but DNA can be transferred from one person to another and from them to somewhere else the original person may never have been.

There are a limited number of providers of this controversial technology; testimony is only allowed in a few countries at present and because many samples come from “cold cases,” forensic scientists often work with degraded or sub-microscopic volumes of material.

After the acquittal on all charges of Sean Hoey in the 1998 Omagh Bombing Trial in Belfast, Northern Ireland in which 29 people died, the future of LCN DNA looks uncertain.

In the United Kingdom, the Association of Chief Police Officers (Acpo) announced that it was suspending the use of LCN testing in all future cases pending the outcome of a the Crown Prosecuting Services review. All current cases in the United Kingdom in which Low Copy Number (LCN) DNA testing forms part of the evidence will be now be scrutinized.

"They were warned about it," said Professor Jamieson, of the Glasgow-based Forensic Institute. He said the Midlands-based Forensic Science Service (FSS) which claimed that they were leading the field through their LCN DNA work should have been asking during the Omagh bombing Trial why no-one else, including the well-resourced FBI, was relying on the same technique. (ForensicScience Suite 101)