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Published on: March 9, 2015
[Validation of Differential Extraction Kit in forensic sexual assault cases]
1Key Laboratory of Forensic Evidence and Scene Technology, Shanghai Key Laboratory of Crime Scene Evidence, Public Security Bureau of Shanghai, Shanghai 200083, China. wdmd305@yahoo.com.cn
Objective:
To evaluate the validity of Differential Extraction Kit in isolating spermatozoa and epithelial cell DNA from mixture samples.
Methods:
Selective lysis of spermatid and epithelial cells combined with paramagnetic particle method were applied to extract the DNA from the mock samples under controlled conditions and forensic case samples, and template DNA were analyzed by STR genotype method.
Results:
This Differential Extraction Kit is efficient to obtain high quality spermatid and epithelial cell DNA from the mixture samples with different proportion of sperm to epithelial cell.
Conclusion:
The Differential Extraction Kit can be applied in DNA extraction for mixed stain from forensic sexual assault samples.
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