植物DNA混合物中物种成分实时荧光PCR定量分析

Plant species quantification in DNA mixtures by real-time polymerase Chain reaction

目的：建立植物DNA混合物中物种成分实时荧光PCR定量方法。方法：建立PCR反应管中某物种DNA质量和该物种特异性基因扩增Ct值之间的定量关系,通过260 nm处光密度值的测定计算DNA提取液的浓度和DNA总质量,并以某物种DNA和总DNA的质量百分比表示该物种DNA含量。对56个待测样品中的物种成分进行定量测定以验证新建方法的准确性和精密度。结果：新建方法的LOQ低于0.51%;B ias为0.00%～20.79%,RSD为0.43%～19.64%。结论：新建方法的准确度和精密度均符合现行要求。

Objective： To develop a model for plant species quantification in DNA mixtures by real - time polymerase chain reaction. Methods： Direct quantitative relation between the DNA mass of a certain species in PCR reaction and the Ct values of corresponding species - specific gene was established. By the measurement of optical density at 260 -nm ultraviolet ray （UV） , DNA concentration and the total DNA mass of DNA extract was obtained. The content of a certain species DNA was expressed as the mass% of target species DNA to the total DNA in sample. The content of a certain species DNA in 56 tested samples were quantified to estimate the accuracy and precision of the novel model. Results ： The limit of quantification （LOQ） of the novel model was lower than 0. 51%. The bias varied from 0.00% to 20. 79%, and the repeatability standard deviation （RSD） varied from 0. 43% to 19.64%. Conclusion： Both the accuracy and precision of the novel model meet the exist requirements.