The content of first-strand products in the PCR reaction

Possible reasons: * freezing cryo tube quality of the RNA template * Overestimation of the mRNA concentration * Reverse transcriptase inhibitors or insufficient reverse transcriptase in the reaction system * Isotope 32 expired * Excessive reaction volume Large, should not exceed 50 uimes; 104. Smear bands are generated * The content of first-strand products in the PCR