Preliminary DNA identification for the tsunami victims in Thailand

The 2004 Southeast Asia Tsunami killed nearly 5,400 people in Southern Thailand, including foreign tourists and local residents. To recover DNA evidence as much as possible from the seriously decomposed bodies, we explored procedures of sample preparation from both bone and tooth samples as well as both mitochondrial and nuclear markers. Despite having failed to recover enough DNA for nuclear marker typing, we succeeded in obtaining fully informative results for mitochondrial markers (HV1 and HV2) from 258 tooth samples with a success rate of 51% (258/507). Using an organic DNA extraction method coupled with an ultrafiltration step, we obtained 16 STR (including 13 CODIS loci, one sex discrimination locus, and two Identifiler loci) profiles for 834 samples with a success rate of 79% (834/1,062). In addition, by comparing the allelic frequencies between the typed samples as a group and other index populations, we conclude that the Thai tsunami victims are a combined group of several populations. Our results provide valuable evidence and protocols for the future forensic practice.