Effect of 11-year storage of GMO reference material at ultra-low temperature on nucleic acid detection of standard matrix sample of transgenic crop.

Reference material is indispensable for the reliability, comparability, and accuracy of transgenic detection results. In this paper, the effects of long-term preservation of matrix reference materials on PCR detection and the stability of low content reference materials were studied. The reproducibility and quantity stability of transgenic reference materials and transgenic samples with different contents were detected by three methods (common qualitative PCR, real-time fluorescent PCR, and droplet digital PCR). The result showed that the transgenic reference material with 0.1% GM content could still be clearly amplified after 9 years of storage, and the Ct value was about 36. The digital PCR revealed that the quantity of GM matrix reference materials remained stable for long storage time. There was no effect on the detection of transgenic elements in sample mixed with soybean, corn and rice powder which stored at -70 to -75 °C for 11 years. In summary, the long-term storage of GM matrix reference materials at low temperature would not affect the detection of each transgenic component and its application as a positive control for transgenic nucleic acid detection. [ABSTRACT FROM AUTHOR]