Two strains of Escherichia coli were studied to determine the effect of constitutive expression of the SOS DNA damage repair response on the activity of ribonucleotide reductase. Activity of the reductase and cellular deoxynucleoside triphosphate (dNTP) pools were both determined before and after exposure of the cells to ultraviolet radiation. The experiments showed no significant difference in enzyme activity or cellular dNTP pool levels between normal E. coli and cells constitutively expressing the SOS DNA damage repair response. Although the SOS response and proportional accumulation of dNTPs both lead to DNA mutation, the occurrence of the latter after a damage event is not controlled or promoted by the first. Cellular DNA damage due to ultraviolet light is of concern to humans because it can lead to skin cancer. In addition to laboratory research, the topic of skin cancer in the Western world was also examined. Data from cancer indices and journal articles were used to analyze the incidence of non-melanoma and malignant melanoma skin cancers. Studies analyzing the awareness of skin cancer amongst the populations of several Western nations were also discussed. The attitudes of people toward skin cancer and sun exposure were found not to correlate with statistical risk of developing the cancer.