dPCR的发展历史、原理及其应用(3)

　　3.5转基因成分检测。
　　
　　传统的qPCR方法可以对食品中的转基因成分进行测定[32,33],由于该方法需要建立标准曲线，加上食品与作物等复杂样品中抑制剂对PCR扩增效率的影响，使qPCR对于低丰度的转基因成分的检测有很大的局限[34].有研究利用dPCR定量转基因MON810与参考基因hmg基因拷贝数的比值，定量结果与qPCR相同[35].2013年，Morisset等[36]利用微滴式dPCR双重检测转基因MON810和参考基因hmg拷贝数比值，微滴式dPCR检测hmg和MON810的线性范围分别为：5~118 000拷贝/反应和6~4 340拷贝/反应，检测的线性范围较宽，能满足常规转基因成分检测的要求。有研究报道dPCR检测转基因成分的灵敏度为0.1%,低 于 欧 盟 规 定 转 基 因 成 分 的 检 出 限0.9%[37].研究表明dPCR可以作为常规的检测技术应用于转基因成分鉴定。
　　
　　4结语与展望。
　　
　　dPCR作为核酸定量的新技术，与此前的核酸定量方法相比，方法的灵敏度、准确度更高。dPCR为分子生物学、微生物学等领域提供了新的检测方法和实验思路。从应用的范围、实验的成本角度来看，dPCR不可能完全取代qPCR,但是dPCR方法可以进行精准的绝对定量分析，极好的数据重现性，而且样本需求较低，在核酸检测与定量等方面有非常重要的补充。在整个dPCR的发展过程中，应用越来越广泛，在核酸检测定量、抗病毒治疗监测、预后判断具有重要的意义。随着dPCR技术和商品化平台的发展，dPCR的通量将会更高，成本更低，在科学研究领域将会发挥更重要的作用。
　　
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