转基因玉米MIR604基体标准物质研制

转基因生物安全监管是生物技术产业健康发展的保障,而转基因检测标准物质是进行转基因监管检测的物质基础,缺少标准物质就难以保证检测数据的准确性、可靠性和可比性。转基因玉米MIR604是我国批准进口用作加工原料的转基因品种,对其安全监管亟须制备标准物质。本项目通过对转基因玉米MIR604种子进行原材料鉴定、研磨、过筛、含水量测定等步骤,制备出转基因玉米MIR604纯品基体标准物质。均匀性检验和稳定性检验结果表明,本批标准物质在瓶内和瓶间均具有良好的均匀性,可在常温下运输1个月,长期稳定性达到6个月,量值稳定。本批标准物质的特性量值为转基因DNA与总DNA的拷贝数比值,由9家实验室采用MIR604/Adh1二重数字PCR联合定值,量值为0.50。充分评估了标准物质定值结果的各个不确定度分量,合成扩展不确定度为0.06 (copy/copy)。本批标准物质规格为1 g瓶–1,使用时最小取样量为100 mg,可用于转基因玉米MIR604的安全监管和定量标识、以及实验室质量控制等领域。

Development of genetically modified maize MIR604 matrix reference materials

The safety supervision of genetically modified organisms (GMO) is the guarantee for the healthy development of the biotechnology, and the reference materials (RM) are the material basis for GMOs detection. The lack of RMs makes it difficult to ensure the accuracy, reliability and comparability of the test data. GM maize MIR604 is approved for import as a raw material in China. The safety supervision of GM maize MIR604 urgently requires to prepare RMs. The pure GM maize MIR604 matrix RMs were prepared through the steps of raw material identification, grinding, sieving and water content determination. The results of homogeneity test and stability test showed that the RMs in this batch had good homogeneity within the bottle and between the bottles, the property value of the RMs was stable, allowing them to be transported at room temperature for one month, as even for six months verified by the long-term stability test. The copy number ratio of the transgenic DNA to the total DNA was collaboratively characterized by nine laboratories using the duplex digital PCR of MIR604/Adh1. The certified value was 0.50. The various uncertainty components of the RM characterization results were fully evaluated, and the expanded uncertainty was combined to be 0.06 (copy/copy). The specification of RMs of this batch is 1 g bottle ^-1 and the minimum sample size is 100 mg. This batch of RMs can be used in the fields of safety supervision and labelling of MIR604, and laboratory quality control.