DNA molecules normally exist as paired strands arranged in a spiral staircase, but sometimes they form knotty clumps called quadruplexes. This happens most often along stretches of DNA with repetitive sequences of the molecule’s nucleotide bases.
At least in test-tube experiments, such quadruplexes are unusually common in regions of DNA that host genes implicated in cancer. The formation of quadruplexes, scientists speculate, could lead to activation of cancer-promoting genes.
Log in
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.