What is the difference between PCR-based miRNA detection and nanopore-based detection?

PCR (polymerase chain reaction) is the standard method for measuring miRNA in most clinical tests. It works by making millions of copies of the RNA molecule (amplification) and then quantifying the amplified product. PCR has high sensitivity but introduces a critical flaw: amplification creates exponential variation — small differences in the starting material become large differences in the final measurement, creating wide data spread that forces score-based interpretation. Nanopore detection (the Yenos method) measures each individual miRNA molecule as it passes through a nanopore, generating a distinct electrical signal — no amplification needed. Because there is no amplification error, the measurement is far more precise, enabling the hard threshold (1.5× HL) that PCR-based methods cannot achieve.