The GScript One-Step RT-PCR Kit provides a convenient and sensitive method for cDNA synthesis and PCR amplification which are combined in a kit using genespecific primers and target RNAs from either total RNA or mRNA. The kit consists of two major components: GScript Enzyme Mix and 5X Reaction Mix. The GScript Enzyme Mix is a recombinant Moloney Murine Leukemia Virus (M-MLV) transcription polymerase (RTase) and hot-start Taq DNA polymerase. The M-MLV is expressed in E. coli and purified to homogeneity, it has lower RNase H activity and high thermal stability, is widely used to synthesize first-strand cDNA at temperatures up to 55°C with increased specificity, higher yields of cDNA, and more full-length product than other reverse transcriptases. It can generate cDNA from 100 base pairs (bps) to 12 Kilo base pairs (kbps). The hot-start Taq DNA polymerase property of the enzyme preparation is conferred by thermolabile monoclonal antibodies that render Taq DNA polymerase inactive until the initial PCR step. The 5X Reaction Mix buffer contain most necessary chemistry for both reverse transcription and PCR amplification in a single reaction tube is optimized for PCR.