TABLE 1.

Intra-assay variability of the two-stage Alu PCR amplificationa

IS (proviruses/reaction)Mean amplificationb (fold, n = 6 assays)SD (fold)% Variation in amplification
3,60012,5001,25010
1,20027,0001,3005
40061,0003,7006
13379,0001,9002
4484,00013,00015
1591,00017,00019
586,00019,00022
  • a Six samples of each dose of IS were independently subjected to Alu-gag preamplification followed by quantitative real-time PCR amplification of HIV-1 LTR DNA. Amplification values in boldface represent the linear range of this particular assay.

  • b Amplification factors of ∼10,000 are usual. An additional 10-fold variation in this value can be observed, depending on the particular lot of Platinum Taq DNA polymerase used.