Fig. 7. Sequence variation of the 3′ overhang of siRNA duplexes. The 2 nt 3′ overhang (NN, in grey) was changed in sequence and composition as indicated (T, 2′-deoxythymidine; dG, 2′-deoxyguanosine; asterisk, wild-type siRNA duplex). Normalized interference ratios were determined as described in Figure 1. The wild-type sequence is the same as depicted in Figure 4.