硅藻硝酸消化法与浮游生物16S rDNA PCR法在溺死鉴定中的比较

目的比较和探讨硅藻硝酸消化法与浮游生物16S rDNA PCR法在溺死鉴定中的应用价值。方法收集40例温州医科大学法医学系2010—2011年受理并证实溺死的鉴定案件,每例案件标本包括肺、肾、肝及现场水样4份样本,分别运用硅藻硝酸消化法与浮游生物16S rDNA PCR法对标本进行检验,硅藻硝酸消化法和浮游生物16S rDNA PCR法所需各器官检材量分别为约20g和2g,现场水样分别为15mL和1.5mL,从所需检验时间以及检出率等方面进行比较分析。结果硅藻硝酸消化法检出硅藻主要为中心硅藻纲和羽纹硅藻纲,浮游生物16S rDNA PCR法可扩增出一条162 bp的条带。平均检验每例案件所需的检验时间,硅藻硝酸消化法为(95.30±2.78)min,少于浮游生物16S rDNA PCR法(325.33±14.18)min(P0.05)。两种方法对现场水样及肺样本的检出率均为100%,而对肝及肾样本的检出率,浮游生物16S rDNA PCR法均为80%,高于硅藻硝酸消化法40%和30%(P0.05)。结论在溺死的法医学鉴定中,应根据具体情况来挑选合适的实验室检验方法。与硅藻硝酸消化法相比,浮游生物16S rDNA PCR法具有检材用量少、信息量大、特异性高等特点,有一定的推广和实践价值。

Comparative Analysis between Diatom Nitric Acid Digestion Method and Plankton 16S rDNA PCR Method

Objective To com pare and explore the application value of diatom nitric acid digestion method and plankton 16S rDNA PCR method for drow ning identification. Methods Forty drow ning cases from 2010 to 2011 were collected from Department of Forensic Medicine of Wenzhou Medical University. Sam ples including lung, kidney, liver and field water fromeach case were tested with diatom nitric acid digestion method and plankton 16S rDNAPCR method, respectively. The Diatom nitric acid digestion method and plankton 16S rDNAPCR method required 20 gand 2g of each organ,and 15 mL and 1.5 mL of field water, respectively. The inspection time and detection rate were com pared between the two methods. Results Diatom nitric acid digestion method m ainly detected two species of diatom s, Centriae and Pennatae, while plankton 16S rDNA PCR method am plified a length of 162 bp band. The average inspection time of each case of the Diatom nitric acid digestion method was （95.30±2.78） min less than （325.33±14.18）min of plankton 16S rDNA PCR method （P〈0.05）.The detection rates of two methods for field water and lung were both 100% . For liver and kidney, the detection rate of plankton 16S rDNA PCR method was both 80% , higher than 40% and 30% of diatom nitric acid digestion method （P〈0.05）, respectively. Conclusion The laboratory testing method needs to be appropriately selected according to the specific circum stances in the forensic appraisal of drow ning. Com pared with diatom nitric acid digestion method, plankton 16S rDNA PCR method has practice values with such advantages as less quantity of sam ples, huge inform ation and high specificity.