[DNA genetyping of the trace bloodstains on the adsorbent object].

OBJECTIVE: To study the extraction and analysis of DNA from trace bloodstains on the adsorbent object. METHODS: DNA was extracted by Chelex-100, QIAamp Mini Kit, and modified QIAamp Mini Kit, respectively. The extracted DNA was amplified and short tandem repeat (STR) loci were genotyped by multiplex PCR procedures, and then analyzed by ABI 3100 Genetic Analyzer. RESULTS: The STR loci could be better genotyped with modified QIAamp Mini Kit, compared to poorer genotyping results obtained with Chelex-100 extraction method and QIAamp Mini Kit. CONCLUSION: Our data indicate that DNA extracted from trace bloodstains on adsorbent object with modified QIAamp Mini Kit serves a better DNA template. for amplification and genotyping.