A Novel Quantification Method for Gene-Edited Animal Detection Based on ddPCR.

As gene-editing technologies continue to evolve, gene-edited products are making significant strides. These products have already been commercialized in the United States and Japan, prompting global attention to their safety and regulatory oversight. However, the detection of gene editing still relies on qPCR, and there is a lack of quantitative detection methods to quantify gene-editing components in products. To ensure consumer safety and transparency, we developed a novel droplet digital PCR (ddPCR)-based detection method for gene-edited products. Primers and probes were designed targeting the editing sites of MSTN-edited cattle, and the method was evaluated for specificity, sensitivity, real sample testing, and detection thresholds. Our results demonstrate that this ddPCR method is highly specific, with a detection limit of 5 copies/µL, and it successfully detected MSTN edits in all 11 tested samples. Tests using both actual gene-edited cattle samples and plasmid DNA at concentrations of 5%, 1%, and 0.01% yielded consistent results, indicating the method's suitability for real-world applications. This ddPCR assay provides a sensitive and specific tool for detecting MSTN gene-edited cattle and determining the presence of gene-edited products, offering crucial support for regulatory monitoring of gene-edited animal-derived foods.