Digital PCR as a Highly Sensitive Diagnostic Tool: a Review

Digital PCR (dPCR) is a nucleic acid quantification method that is widely used in genetic analysis. One of the most significant advantages of dPCR over other methods is the possibility of absolute quantitative determination of genetic material without construction of calibration curves, which allows one to detect even single molecules of nucleic acids, and, hence, provides early diagnosis of diseases. One specific characteristic of dPCR is the detection of the analyzed biological object in each microreaction, followed by the presentation of the analysis results in a binary system, thereby giving the method its name. The key aspects of developing the dPCR method, i.e., from the first devices based on microfluidic chip technology to modern systems capable of measuring a target at a concentration of up to 1 in 100000 copies are shown in the current work. We analyzed the data on the detection of various pathogens using dPCR, as well as summarizing various study results demonstrating the innovativeness of this method. Both the possibilities of multiplex dPCR analysis and its potential in clinical practice are presented. This review also addresses the issue of the role of dPCR in the development of noninvasive methods for analysis of oncological diseases. Possible ways of developing dPCR technology were emphasized, including its use as a "point-of-care" system.