Determination of Damage and Repair in Specific DNA Sequences

Abstract We describe here the methodology developed in our laboratory to study the frequency and repair of cyclobutane pyrimidine dimers induced by ultraviolet light (254 nm) in the individual strands of specific DNA sequences. We have used this technique to establish the direct correlation between transcription by RNA polymerase II and the preferential repair of the transcribed strand of an active gene in mammalian cells. The approach has similarly been applied to bacteria and to yeast, as detailed for those respective systems.