DNA profiling mistake prompts re-test of criminal cases

DNA profiling mistake prompts re-test of criminal cases by Sara Grosse 08:17 PM Jan 03, 2012 SINGAPORE - A mistake made in a DNA profiling laboratory has resulted in some criminal cases having to be re-tested. The Health Sciences Authority is re-testing DNA samples of 87 criminal cases, as a precautionary measure. This comes after HSA's DNA Profiling Laboratory discovered in August last year, that a reagent of higher than usual concentration, had been used in the tests. HSA said the incident arose from a new method of preparation being used. The laboratory manager had misread the label and used a stronger concentrate for dilution, resulting in the mistake. The reagent of higher than usual concentration was used as part of the DNA testing process between October 2010 and August 2011. HSA said however the scientific impact of the reagent is minimal. That's because the use of the reagent would not have resulted in false positives, leading to the wrongful identification of a person. Separately, the Attorney-General's Chambers has reviewed the 412 criminal cases, both concluded and ongoing, that were affected by this incident. It has requested the re-testing of only 87 ongoing cases. The AGC said in these cases, the DNA test results may be relied upon by the Prosecution, the Defence or the courts. It added the DNA test results of the 278 criminal cases that were concluded in court, did not materially impact the resolution of the cases. Since the incident, HSA now purchases pre-prepared reagents. A committee has been set up to review HSA's processes, systems and follow-ups, related to the incident. The committee is expected to submit a report after the re-testing of the 87 cases, which is expected to be completed by March.