Micro-droplet digital PCR (polymerase chain reaction) quantitative determination method of CHO (Chinese hamster ovary) cell gene copy number

The invention discloses a micro-droplet digital PCR (polymerase chain reaction) quantitative determination method of CHO (Chinese hamster ovary) cell gene copy number. The method comprises the following steps: 1) extracting genome DNA of CHO cells; 2) enzymatically digesting the genome DNA by virtue of restriction enzyme; 3) conducting a micro-droplet digital PCR reaction; and 4) after the PCR reaction, determining the numbers of positive micro-droplets and negative micro-droplets of a sample in each pore of a PCR reaction board, so that the gene copy number of the CHO cells is obtained. The invention also discloses a primer and a probe applied to the method. The determination method disclosed by the invention, by selecting proper reference genes, designing proper primer and fluorescence labeled probe, optimizing the sample loading quantity of the CHO cell genome, selecting proper restriction enzyme to conduct enzymatic digestion on the genome template and evaluating the influence of various genome extraction kits on a ddPCR detection result, improves the sensitivity and the precision of the micro-droplet digital PCR absolute quantitative determination method of the CHO cell gene copy number.