指甲游离缘的核DNA分型研究

Extraction and analysis of nuclear DNA from free margin of nail material

为探讨指甲游离缘核DNA分型的可行性,采集无关个体指甲游离缘样本10份,分别以不同消化体系,采用有机法、Chelex-100法,有机法结合Chelex-100法等3种方法提取指甲游离缘核DNA,AmpFlSTR IdentifierTM试剂盒复合扩增,ABI PRISM3130自动遗传分析仪检测分析。结果显示:与对照血样比较,有机法结合Chelex-100法提取的样本核DNA均获得满意的STR分型,有机法提取的样本核DNA可以进行STR分型,但部分样本图谱峰值不均衡,Chelex-100法提取的样本核DNA不能分型或出现较多等位基因缺失。提示指甲游离缘可以进行成功地核DNA的分型,有机法和有机法结合Chelex-100法提取的DNA质量都可成功检测,其中以有机法结合Chelex-100法提取DNA的检测成功率最高。

To investigate the feasibility of DNA analysis from free margin of the nail, genomic DNA was extracted from the free margin of nail clipping of 10 volunteers using the proteinase K/SDS -based organic method, the Chelex-100 method, or a combined method. Target DNA was simultaneously amplified using a fluorescent multiplex AmpF1STR Identifier^TM kit. The PCR products were analyzed on the ABI PRISM 3130 Genetic Analyzer. The results showed that, compared with profiles achieved by genotyping of blood samples from each volunteer as reference, 100% concordance was achieved using the combined method. The STR genotype profiles obtained through the organic method were acceptable, despite preferential amplification at some loci. In contrast, no readable profiles could be determined when DNA was extracted by the Chelex- 100 method, and there were a large number of alleles missing. Our data suggest that free margin of nail can be used for nuclear DNA analysis, but the type of DNA isolation method used is critical. The traditional organic extraction method works reasonably well for free margin nail DNA isolation, and combination of organic extraction and the Chelex-100 method works best.