FTA-DNA直接提取法的研究与应用

A simple and rapid modified-new method for DNA extraction of FTA bloodstains

目的建立一种简约且易于自动化操作的Whatman FTA卡血样DNA提取方法。方法取直径1．2mm FTA卡血样，分别用FTA-DNA直接提取法及FTA常规提取方法提取DNA，AB-Identifiler^TM试剂盒分别进行10山和25山体系检测比较，并筛选批量grA卡血样DNA自动化提取程序。结果200份grA卡血样分别采用2种方法提取DNA模板，25μl体系PCR-STR检测，分型结果均良好。10μl体系检测，FTA-DNA直接提取法优于FTA常规提取方法，图谱RFU值为1000～2000，采用自动化工作站运行该提取程序较手工操作DNA分型图谱均衡性更佳；采用FTA常规提取方法检测，图谱RFU值100～2000，小片段优先扩增现象明显，且有19％的样本出现丢峰现象，采用自动化工作站运行该程序对其结果改善不明显。经工作站运行FTA-DNA直接提取法自动程序及10山体系检测本2万余份FTA卡采集的血样，均获得16个STR基因座DNA分型结果。结论本文建立的FTA-DNA直接提取法适用于FTA卡血样自动化DNA建库。

Objective To establish a simple and rapid new method for DNA extraction of FTA bloodstain samples. Methods Genomic DNA was extracted from FTA bloodstains of 1.2mm diameter by FTA-DNA direct extraction and FTA routine method respectively, and their genotypes were analyzed using ABI IdentifilerTM kit in 10μl and 25μl of reaction volume respectively. Results For 25μl of reaction volume, all DNA extracted by two different methods was successfully genotyped. For 10μl of reaction volume, however, the typing success rate of DNA extracted by FTA routine method was significantly lower than those by FTA-DNA direct extraction procedure. Using FTA routine method, the value of RFU ranged from 100 to 2000, and the peak imbalance result from preferential amplification of the smaller allele was a com- mon phenomenon. Moreover, allelic dropout occurred in approximately nineteen percent of samples, and this was not obviously improved even if performed by automatic DNA workstation. However, using FTADNA direct extraction procedure, the typing results were similar to those in 25 μl of reaction volume, and better results can be obtained using automatic DNA workstation. Conclusion The FFA-DNA direct extraction method is simple and rapid, and can be used to automatic establishment of DNA database with FTA bloodstains.