中文摘要：

目的建立盐析法快速从口腔拭子中提取基因组DNA的方法。方法首先以细胞裂解液和蛋白酶K消化口腔上皮细胞,然后用5 mol/L NaCl沉淀蛋白质,用异丙醇沉淀DNA,最后用70%乙醇洗涤得到的DNA并将其溶于TE（10mmol/L Tris-HCl,1 mmol/L EDTA,pH 8.0）中。用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）技术对TP53基因的rs1042522和CHRNA3基因的rs12910984位点进行分型。对不同基因型的样本测序验证。结果单支口腔拭子提取得到的DNA量在0.68～2.56μg之间,D260/D280比值在1.77～1.94之间。经PCR扩增和酶切消化,10个样本的两个单核苷酸多态性都得到了清楚分型。酶切结果与测序结果吻合。结论本实验所建立的盐析法可以快速、简便、经济地从口腔拭子得到高质量的基因组DNA。

英文摘要：

Objective To establish a rapid salting out method for extraction of genomic DNA from buccal swabs.Methods Buccal epithelial cells were digested with cell lysate solution and proteinase K solution.Then the proteins were removed by salting out and centrifugation and DNA was precipitated with isopropyl alcohol.Finally,the precipitations of DNA were washed with 70% ethanol and were resuspended in TE.The rs1042522 loci of TP53 gene and rs12910984 loci of CHRNA3 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism（PCR-RFLP） technique.The samples with different genotypes were confirmed by direct sequencing analysis.Results The DNA yield of single buccal swab ranged from 0.68 to 2.56 μg;the D260/D280 value ranged from 1.77 to 1.94.After PCR amplification and enzyme digestion,two single nucleotide polymorphisms（SNPs） of 10 samples were clearly genotyped.The results of PCR-RFLP agreed well with the results of direct sequencing.Conclusion The present salting out method is rapid,simple,and economical for DNA extraction from buccal swabs.The obtained genomic DNA is of high quality.