Triplet photosensitization and the photobiology of thymine dimers in DNA.

The knowledge of the energy levels of the lowest triplet states of the DNA constituents obtained from photophysical experiments has allowed the design of a photochemical technique which introduces a specific change in the DNA structure, the dimerization of adjacent thymine residues, which, in turn, has led to important conclusions about the role of thymine dimers in the u.v. photobiology of T4 phage and insight into the mechanism of u.v. induced mutations.