3种甲醛固定组织DNA提取方法的比较

目的对不同方法提取甲醛固定组织中DNA的效果进行比较,寻找一种操作简便、经济实用、质量较高的DNA提取方法。方法取甲醛固定的心肌组织14份,分别以改良酚-氯仿法,改良Trizol法,试剂盒法提取DNA,进行紫外分光光度计测定OD260/OD280值后,经PCR扩增,琼脂糖凝胶电泳分析确定提取的DNA质量。结果改良酚-氯仿法,改良Trizol法,试剂盒法OD260/OD280比值分别为1.841 5±0.380 4、1.370 5±0.336 7、0.831 6±0.175 0。两两比较均有显著性差异(P<0.05)。3种不同方法提取DNA含量分别为0.943 8±0.530 1、0.707 5±0.423 6、0.342 8±0.182 5。PCR扩增后琼脂糖凝胶电泳显示以改良酚-氯仿法所提DNA的谱带清晰度好于其它两种方法。结论改良酚-氯仿法简便有效,所用试剂价格低廉,是一种经济实用的甲醛固定组织DNA提取方法。

Comparison of different methods for DNA extraction from formaldehyde fixed tissues

Objective To compare the effect of different methods for DNA extraction from formalin-fixed tissues,and look for a simple,economical and practical method for DNA extraction from formalin-fixed autopsy tissues.Methods Genomic DNA of 14 formalin-fixed myocardial tissues was extracted by the modified phenol-chloroform method,modified Trizol method and DNA extraction kit respectively,and their concentration and quality were measured by using UV spectrophotometer at 260nm and 280nm.After PCR amplification with GAPDH primers,the products was analyzed by agarose gel electrophoresis.Results The ratios of OD260/OD280 with the modified phenol-chloroform method,modified Trizol method and DNA extraction kit were 1.841 5±0.380 4,1.370 5±0.336 7 and 0.831 6±0.175 0,respectively,and there were a significant difference(P<0.05) when compared with each other.The yields(μg) of DNA extracted by three different methods were 0.943 8±0.530 1,0.707 5±0.423 6,0.342 8±0.182 5,respectively.Agarose gel electrophoresis of PCR products showed that the DNA bands obtained from the modified phenol-chloroform method were more clear than that from the other two methods.Conclusion The results demonstrated that the modified phenol-chloroform method is an optimal method for DNA extraction from the formaldehyde fixed tissues.