duadruplex-interactive drugs
Since 1962, special sequences in DNA that can form secondary DNA structures - such as four-stranded structures in which consecutive runs of guanines are found - have been observed.
These remained structural curiosities until the late 1980s, when biological roles for these structures were proposed.
More credence was given to these ideas when proteins were discovered that either bind to the preformed secondary structures or are involved in the formation or resolution of these structures.
Their possible role in regulating the activity of telomerase through formation of G-quadruplex structures led to the first effort to target these unusual DNA structures