法医DNA实验室的DNA污染和防范

DNA污染是产生DNA鉴定结论错误的重要因素,法医DNA实验室要努力去解决这一问题。DNA污染有自身污染、交叉污染、PCR污染3种。法医DNA实验室要采取实验室分区、严格检验操作步骤、对试剂及消耗材料进行质量控制等方法防止发生DNA污染,采取设置对照样本、核查DNA结果、建立DNA排查数据库等方法监测和发现DNA污染。

Preventing DNA contamination in a forensic DNA laboratory

DNA contamination is an important factor in the investigation of a wrong DNA result.A forensic DNA laboratory should endeavor to solve this problem.There are three main sources of exogenous DNA:1)DNA from the analyst,2)DNA from other samples in the lab,and 3)PCR products or fragments of the allelic ladder.They cause self-contamination,cross-contamination and PCR contamination,respectively.To prevent contamination,separating operation regions,founding effective protocols and quality controlling of key reagents and consuming materials should be carried out.To monitor contamination,setting up control samples,checking the DNA results and establishing DNA elimination databases should be performed in a forensic laboratory.