ZHU Chuan-hong, ZHENG Dao-li, NI Rao-zhi, WANG Hai-sheng, NING Ping, FANG Hui, LIU Yan
Forensic Science And Technology. 2012, 37(6): 13-16.
Abstract (
)
Download PDF
HTML
Knowledge map
Save
Objective To investigate DNA analysis and DNA quantification of samples treated with the agents of benzidine tests. Methods Bloods of ten peoples were collected, and bloodstains were made on the filter paper. The same size and amount bloodstains were made by BSD600-DUET Paper Hole Puncher. Six experimental groups are divided by samples for 30min, 1h, 3h, 6h, 12h and 24h after samples treated with benzidine. Template DNA of samples were extracted by three DNA extraction methods(magnetic bead-based DNA extraction protocol,QIAamp DNA Investigator Kit protocol and Chelex-100 extraction).STR profiling was detected by PCR. DNA quantification of samples treatment was detected by real time PCR. Results The average values of DNA quantification of samples were decreased continuously with times after treatment with benzidine. The linear curves is Y=-0.4087ln(x)+0.7044(R2=0.7633)for the group of magnetic bead-based DNA extraction protocol),Y=-0.2393ln(x)+0.4764(R2=0.8715)for the group of QIAamp DNA Investigator Kit protocol, Y=-0.1178ln(x)+0.2302(R2=0.9571)for the group of Chelex-100 extraction. Statistical comparisons between each of the groups were made by multiple-ways Analysis of variance with SPSS 19.0 indicated that benzidine can alter DNA amount over time up to 24h(P<0.01), and that DNA amount with different DNA extraction methods have significant differences(P<0.01). DNA typing of 16 locis of 8.33% samples was detected by PCR-STR with Identifiler plus kits and the loss of 232 heterozygosity were detected in 142 samples. Conclusion Benzidine test has significant influence on DNA typing and DNA quantification, so the samples treated by benzidine could not be detected by PCR-STR.