6T2G:
reference: Structure of two G-quadruplexes in equilibrium in the KRAS promoter., Marquevielle J, Robert C, Lagrabette O, Wahid M, Bourdoncle A, Xodo LE, Mergny JL, Salgado GF, Nucleic Acids Res. 2020 May 20. pii: 5841130. doi: 10.1093/nar/gkaa387. PMID: 32432667

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