DNA for forensics
DNA technologies and techniques for forensics
LGC continuously works to develop new DNA technologies for forensics. We offer an extended range of forensic DNA techniques covering all routine and specialist analyses, available on demand.
DNA profiling – PACE DNA
Our PACE laboratory provides rapid, cost-effective DNA profiling of reference samples, with results loaded to the National DNA Database or made available to Reporting Officers for comparison
We have optimised the ESI17 Fast (DNA17) chemistry to enable direct amplification, using state of the art robotics. This gives us the capability to process samples, in real time, in well under 4 hours (fastest reported urgent sample was 3.5hours from receipt). The average laboratory processing time for a batch of 89 samples is 5 hours.
This technology together with effective batching and utilisation of lean workflow techniques ensures we can routinely deliver samples in less than the contracted TRTs and in fact approx 50% of samples are delivered in less than a day. We are also well placed to be able to deliver an urgent service which allows us to process and report results to the NDNAD well inside custody time limits.
In addition to standard reference samples we can also process Biometric Vetting samples and samples relating to Mass Screens.
DNA profiling – Crime Stain and Casework samples
Our DNA Crime Stain team carries out DNA profiling from a wide range of sample types including body fluid stains, hairs, cigarette ends and non-visible traces of DNA. Sweat and skin flakes recovered from the inside of garments and footwear can yield DNA profiles where the identity of the wearer may be in doubt; tools, weapons or any other item that may have been touched during the course of an incident could also be relevant to an investigation.
Our services are noted for exceptionally high success rates, rapid turnaround times and competitive pricing. Success rates are a key driver in any process change carried out within LGC and were instrumental in our selection of ESI17 FAST as our DNA17 profiling chemistry. Our validation work demonstrated that this chemistry had superior capability when dealing with low template DNA samples.
Specialist DNA techniques
In addition to our standard DNA17 profiling line, we have developed and continue to expand a rich portfolio of specialist DNA techniques which, used together, give our scientists the best chance of discovering information from samples of DNA, however small, mixed or degraded. They include:
- Bespoke extraction techniques to recover sperm cells from cold case slides and tapes.
- Criminal relationship testing.
- DNA Profiling from teeth and bones.
- Y-STRs for determining male-only DNA. This is especially useful in mixed male/female samples where sexual assault is alleged (see below for an update to this service).
- Familial searching of the National DNA Database, with results ranked in order of interest.
- Mitochondrial DNA profiling for old or degraded samples or to trace family connections down the female line.
New additions to our range of accredited DNA services
LiRa is LGC’s newly validated mixture interpretation software that uses a discrete interpretation model to quantitatively evaluate DNA evidence. LiRa has been developed in-house and is designed to perform likelihood calculations on complex DNA profiles from up to 3 people.. This software has already demonstrated its capability by allowing a statistical weight of evidence to be calculated in cases where this was previously not possible. Please download
our LiRa fact sheet
for more information.
LGC has also been granted accreditation to use a new and improved Y-STR technology (Promega’s Poweplex Y23 Kit) for determining male only DNA. Y23 offers increased discriminating power and sensitivity as well as an improved ability to deal with inhibited samples. Y-STR profiling can be utilised in a range of case types, but is particularly useful in sexual offence cases. In order to ensure we can readily deliver to an increasing demand for Y-STR analysis, LGC has also increased the number of Reporting Officers trained to deliver this type of work. Y23 is now available as a service from LGC. In addition, we are commencing a pilot to collate success rate information from a range of case types. The results of this pilot will be written up and will be available to download later in 2015.
If you have any questions or would like further information, please contact us