Reproducibility of mtDNA analysis between laboratories: a report of the European DNA profiling group (EDNAP)

The aim of this collaborative exercise was to determine whether uniformity of mtDNA sequencing results could be achieved among different EDNAP laborat ories. Laboratories were asked to sequence mtDNAHV1 region (16024-16365) fr om three bloodstains, proceeding in accordance with the protocol and strate gies currently used in each individual laboratory. Cycle sequencing was use d by 11 laboratories and solid phase single stranded sequencing was used by one laboratory. Different PCR strategies and PCR conditions were used by t he different laboratories. Three laboratories used semi-nested PCR, two nes ted PCR, three direct amplification of HV1 and four amplification of overla pping fragments covering the HVI region. Despite the diversity of methodolo gies used, all the laboratories reported the same results. The successful r esult of this exercise shows that PCR based mtDNA typing by automated seque ncing is a valid, robust and reliable means of forensic identification desp ite the different strategies and methodologies used by the different labora tories. (C) 1998 Elsevier Science ireland Ltd. All rights reserved.