Genome complexity: quantum jitters (Introduction)

by David Turell , Thursday, March 12, 2015, 15:44 (3332 days ago) @ David Turell

Trying to follow how DNA is copied and errors appear. Again reality starts at a quantum level:-"Watson and Crick had originally hypothesized that the bases could nudge hydrogens out of the way to allow mis-matched connections. Aided by the NMR technique, Kimsey provided the first direct evidence for just such an atomic rearrangement in a DNA duplex. He also showed that a similar phenomenon occurs in RNA, the chemical cousin of DNA.-"This tiny movement, or "quantum jitter," takes such an enormous amount of energy that bases are successful at accomplishing the feat only once out of every 10,000 or so attempts. Even then, they can only hold their new shape for a very short period of time—50 to 200 microseconds—before the hydrogens pop back into their original position.-"The researchers looked back at previous biological studies and found that these rare alternative states appeared in the DNA about as often as the polymerase machinery's copying errors.-"'This is a remarkable study that illuminates a fundamental mechanism responsible for the random mutations that drive evolution and contribute to cancer," said Bert Vogelstein, M.D., a cancer researcher at Johns Hopkins University School of Medicine who was not involved in this research."-
 Read more at: http://phys.org/news/2015-03-quantum-jitters-basis-evolution-cancer.html#jCp