Optimization of RT conditions for genotype 1b amplicon 2. R2V1 and R2V2 were RNAs isolated from the same aliquot of a patient plasma; R2V1 employed guanidine thiocyanate and phenol/chloroform extraction and R2V2 employed the Viral RNA Mini Kit. RT primer B4R1 is a specific primer targeted to the 3'UTR. Rndm, random hexamers; M-MLV, Murine Leukemia Virus Reverse Transcriptase; AMV, Enhanced Avian Reverse Transcriptase. Different PCR primers were used for odd or even numbered lanes. Lanes 11 and 12 are negative controls in which template RNA was omitted.