Could UVB rays cause our DNA to oxidize?

Until now, it was considered that the damaging effects of UVB rays on DNA were due to the excitation of the bases, which produces pyramidine dimers. However, an experiment completed under French National Research Agency project OPHID, in which INAC is participating, showed that irradiation of genomic DNA at 295 nm also caused oxidation damage, particularly to the telomeres (DNA sequences located at the ends of the chromosomes).

The findings have raised numerous questions. How are DNA molecules ionized—and not merely excited—by such low energy? Does the phenomenon observed in vitro also occur in vivo? What are the effects on cells and health? We will have to wait a little longer for the answers: Researchers will begin by trying to understand the tipping point between excitation and ionization.

Contact: jean-luc.ravanat@cea.fr

Facebook

Twitter