Scientists Observe DNA ‘Sunburn’

U.S. and German scientists say they have, for the first time, observed DNA being damaged by ultraviolet light.

Ohio State University chemists and their German colleagues at the University of Munich used a special technique to observe the most common chemical reaction among a family of reactions on the DNA molecule that are linked to sunburn. They discovered the key reaction occurs in less than 1 picosecond, or 1 millionth of 1 millionth of a second.

The speed of this reaction has important consequences for understanding how DNA is damaged by UV light, said OSU Associate Professor of chemistry Bern Kohler. In this study, we didn’t see any evidence that long-lived energy states are responsible for damage. Now it seems more likely that short-lived states cause the most common chemical damage to DNA.

The study was conducted by Kohler and Carlos Crespo-Hernandez, a former postdoctoral researcher at Ohio State, in collaboration with Wolfgang Schreier, Tobias Schrader, Florian Koller, Peter Gilch, Wolfgang Zinth, Vijay Swaminathan, and Thomas Carell of the University of Munich.

The study appears in the journal Science.