Reproducibility of real-time quantification PCR chimerism assay.

A total of 47 post–allo-BMT DNA samples were analyzed twice, once on each of 2 separate days. The figure shows results from the second assay (vertical axis) plotted against results from the first assay (horizontal axis). The margin for error is proportional to the value of each genotype fraction (F) and is F ± 0.4 F. This margin for error roughly corresponds to a Ct measurement error of ± 0.5 Ct.