CD wavelength scans for oligos A, B, and C and their corresponding control sequences. CD spectroscopy can be used to differentiate among GQ topologies (e.g., a positive peak at ~264 nm and a negative peak at ~240 nm suggest a parallel component in GQ fold, whereas positive peaks at ~295 and ~245 nm and a negative peak at ~260 nm signify antiparallel component in GQ fold). Mixed-hybrid GQ structure have CD signature between those reported for parallel and antiparallel GQs. According to CD analysis, oligonucleotides containing A, B and C sequences have significant parallel character. In addition, C secondary structure has an antiparallel component.