不同前处理方法提取牙齿DNA的比较

摘要

Objective To com pare the concentration of teeth DNA extracted by three different pretreatm ent m ethods and to explore a sim ple, econom ical and practical pretreatm ent m ethod w ith high concentration of extracted DNA from teeth. Methods A total num ber of 21 m olars w ere collected from 7 corpses. The pretreatm ent of 3 m olars from each individual w as random ly perform ed by tooth crum b m ethod, ball-m illing m ethod and liquid nitrogen m illing m ethod and 50 m g tooth crum b w as w eight and DNA w as extracted by A utoM ate ExpressTM forensic DNA extraction system . Subsequently, the concentration of DNA and corresponding STR genotyping of three m ethods w ere com pared. Results The DNA concentration extracted by tooth crum b m ethod, ball-m illing m ethod and liquid nitrogen m illing m ethod w as 0.055 6-1.989 1 ng/μL , 0.036 6-1.175 6 ng/μL and 0.037 8-1.249 0 ng/μL , respectively. The DNA concentration ob-tained by tooth crum b m ethod w as higher (P<0.05) and the success rate of STR genotyping w as high. Conclusion C om bined w ith A utoM ate ExpressTM forensic DNA extraction system , tooth crum b m ethod is an efficient and feasible m ethod to extract DNA from teeth, w hich can be applied in forensic practice.%目的：对三种不同前处理方法提取的牙齿DNA浓度进行比较，建立一种操作简便、经济适用、浓度较高的牙齿DNA提取的前处理方法。方法选择源自7具尸体的共21颗磨牙，每具尸体的3颗磨牙随机按牙屑法、球磨法、液氮研磨法进行前处理，并分别称取50 mg，采用AutoMate ExpressTM法医DNA提取系统提取DNA，对三种方法提取的DNA浓度和STR分型结果进行比较。结果牙屑法、球磨法和液氮研磨法提取的DNA质量浓度分别为0.0556~1.9891、0.0366~1.1756和0.0378~1.2490 ng/μL，牙屑法提取的DNA质量浓度较高（P＜0.05），且STR分型成功率高。结论牙屑法结合AutoMate ExpressTM法医DNA提取系统是提取牙齿DNA的一种切实可行的方法，可应用于法医学鉴定实践中。