In 1962, researchers at the National Institutes of Health identified peculiar twists of DNA shaped into four-stranded structures, rather than the double helix that had come to define DNA. For much of the 50 years since the discovery of these structures, now known as G-quadruplexes, “it was felt that those findings were a laboratory curiosity, an artifact if you will,” says Stephen Neidle of University College London. Still, researchers were intrigued by these test-tube structures because they were made exclusively from guanines and were stable at physiological conditions. Yet evidence for their existence in human cells remained elusive. “It’s almost become more religion than science,” says Steve Jackson of the University of Cambridge. “Some believed in them, some didn’t.”
To end the debate, Jackson’s lab teamed up with the lab of Shankar Balasubramanian, also at Cambridge. They used a small molecule called pyridostatin, which binds to G-quadruplexes in vitro, ...
