The 2013 Interlaboratory Comparison of Forensic Mitochondrial DNA Typing in Thailand

Abstract

Objective: To evaluate the results of the 2013 interlaboratory comparison of forensic mitochondrial deoxyribonucleic acid (DNA) typing. Material and Methods: The evaluation was divided into 2 parts. (1) Laboratory analysis was assessed using control cell K562 and blood stains from 3 suspects of father-child-mother on membrane. Each laboratory extracted DNA from these samples and performed the test following the standard routine protocol. The results were appended in the given forms and send back to the provider. (2) Hypothetical forensic case studies of grandmother and nieces were asked optionally. Each laboratory could select whether to answer the second part or not. Results: Five laboratories (83%) analysed only hypervariable region I (HV I) and hypervariable region II (HV II) of mitochondrial DNA while only one laboratory (17%) analysed all regions of control region. The report of this interlaboratory comparison showed the average error rate from consensus polymorphism positions of 19% (range 0-37%). Only one laboratory calculated necessary forensic statistical values and showed these values within a report. For the hypothetical forensic case studies, the answers from each laboratory showed several variations. Conclusion: A training workshop on forensic mitochondrial DNA typing should be organized. A standard guideline of the test should be released in order to provide high quality service and reduce inconsistent results among forensic laboratories in Thailand.

Keywords

• forensic
• interlaboratory comparison
• mitochondria dna typing
• thailand