title: Origins of spontaneous base substitutions.
abstract: Although simple to understand, satisfying to the imagination, and compelling as a teaching aid for beginning students, the evidence is mounting that the tautomeric shift is neither a common nor a likely origin for spontaneous base substitutions. Indeed, other sources, such as ionized base mispairings with nonionized bases, wobble of a bases in the DNA, and transient misalignment of bases causing dislocations at pairing sites, have been shown to induce spontaneous base substitutions. On the other hand, among the 4 common bases in DNA, no experimental evidence exists that tautomeric shifts can induce mutations.
authors.affiliation: Department of Genetics, University of Alberta, Edmonton, Canada.
authors.forename: R C
authors.initials: RC
authors.lastname: von Borstel
mesh_terms: D001482:Base Composition; D004247:DNA / Q000737:chemistry / Q000235:genetics; D008957:Models, Genetic; D009154:Mutation
chemical_list: D004247:DNA