Abstract: Objective To validate the analysis capability of RapidHITTM 200 system for four kinds of routine forensic samples and the recyclable capability of template, template DNA and PCR products in the process of twice duplicate detection. Methods The buccal swabs underwent the test twice by RapidHITTM 200 system, and the template DNA and PCR products that arose in the system were also tested for two times. After four kinds of routine forensic samples were detected by RapidHITTM 200 system, the follow-up tests of the template, template DNA and PCR products that arose in the system were performed. Results The STR loci could be detected in the buccal swabs by the system for the first time. However, part of the STR loci lost during the second test. And the peak value obtained in the second test was significantly reduced than the one in the first time. The average STR loci detection rates of the template DNA and PCR products were both less than 50% in the second test, which were significantly reduced than that in the first test. In addition, the analysis capability of the system for the tissues and buccal swabs was better than that for the blood and cigarette butts. Compared with the first test, the STR loci detection rate of the tested items, template DNA and PCR products decreased with the numbers of tests. Conclusion RapidHITTM 200 system is more effective in retesting buccal swabs than other samples, whereas the items, DNA template, PCR products obtained in the first and second time cannot be directly used for the further application and study of forensic medicine.

Key words: forensic genetics, short tandem repeat, RapidHITTM 200 system, consistency checking