Abstract:In order to establish TaqMan Real-Time PCR for detection of GCRV genotype Ⅰ, the primers were designed according to conservative region of S6 as follows:normal primers designed as P1 and P2 with predicted product size of 661 bp, real time primers designed as F1 and F2 with predicted product size of 159 bp, and a probe.Standard curve(Y=-3.389X+38.076) was generated between the cycle threshold(Ct) and standard plasmid(PVAX1-S6) with 10-fold serial dilutions.The results showed that there was a good linear relationship between Ct value and template concentration with a detection range from 3.9×107 to 3.9×101 copies/μL, and the correlation coefficient reached 0.992 while the detection limit of this method was 4 copies/μL for plasmid template.This assay had a specific detection of the GCRV genotype Ⅰ, and had no detection signals to GCRV genotype Ⅱ, Ⅲ and other pathogens.16 suspected grass carp hemorrhage specimens were tested, and 2 more positive samples were detected using this established assay than normal RT-PCR.The developed TaqMan Real-Time PCR detection method for the GCRV genotype Ⅰ with high efficiency, specificity, sensitivity and repeatability is available for clinical rapid detection and quantitative analysis of the GCRV genotype Ⅰ.