Dark energy states in DNA
You’ve heard about the imperceptible dark matter making up much of the universe, you know about the mysterious grey matter of the human brain, why should DNA be any different? Chemists at Ohio State have proven their previously hypothesized "dark" energy states that occur in nucleotides, the building blocks of DNA and RNA. These weird high-energy states are dark because they cannot be detected with the usual UV flourescence techniques. To observe these dark states, the chemists used a technique called transient absorption, which works off the idea that molecules absorb light at specific wavelengths. First predicted by calculations last year, where they were called n(p)*, dark energy states have now been proven to exist in cytosine, thymine and uracil, three of the five bases of the genetic code.
UV light can make DNA mutate, which sometimes leads to diseases like cancer. So, the faster DNA can dissipate UV energy, the less likely it is to take damage. "Bright" energy states last only about a picosecond (a millionth of a millionth of a second), thus posing little risk of mutation, but dark states can last 10-150 picoseconds, in which the molecule unstable and vulnerable. "Now we see that there is a family of energy states in DNA responsible for energy dissipation, and this is a major correction in how we view DNA photostability," Bern Kohler, head of the research team. "The detection of this dark state in single bases in solution increases the chances that it may be found in the DNA double helix."
DNA’s dark side, AstroBio.net
New study sheds light on ‘dark states’ in DNA, PhysOrg.com