Figure 2.

RNase H1 mutations A185V and V142I together impair primer processing at OriL in vivo. PEx analysis of the OriL region (shown in top panel) in RNase H1 patient fibroblast (PF) and control fibroblast (CF) DNA. Samples were (+) or were not (–) treated in vitro with E. coli RNase H before PEx analysis. The sequence (in bold) where RNA-DNA transitions have been previously mapped (45) is shown to the right. Shorter products mapping to the known RNA–DNA transitions downstream of OriL accumulated in the RNase H-treated samples.