The invention provides methods of preventing or treating a conditionassociated with DNA damage in an animalcomprising the administration of a substance that interferes with the activityof the CUL4A ubiquitin ligase. The invention alsoprovides a substance that interferes with the activity of CUL4A, as well ascompositions comprising the interfering substance anda carrier. The substance of the invention preferably enhances nucleotideexcision repair activity in an animal. The inventionfurther provides methods of identifying substances that negatively orpositively modulate the expression and/or activity of CUL4A.
