Fig. 3

Two step RT-ddPCR test with reduced SSIII RT amount. SSIII RT enzyme was reduced to 20 U in each RT reaction. The condition combinations were: SSIII RT with gene specific priming (a buffer background; b SIV RNA standard spike); SSIII RT with random hexamer priming (c buffer background; d SIV RNA standard spike). The ddPCR step of all reactions was performed with MGB probe assays. Detailed experimental conditions are listed in Table 1. Note that in control reactions (a, c) there were background signals in putative SIV target signal region. Quantitation was not done due to background signals. Random hexamer priming yielded significantly fewer ddPCR signal counts compared to gene-specific priming (compare d to b)