"Cell or Molecular Dysfunction"^^ . "A relatively common point mutation in which a purine is exchanged for a nonidentical purine or a pyrimidine is exchanged for a nonidentical pyrimidine. Base mispairing and mutagenic chemicals including nitrous acid and 5-bromo-2-deoxyuridine can result in transitions.NCI" . "Mutation, TransitionSYNCI" . "TransitionSYNCI" . "Transition_Mutation"^^ . . "C18134"^^ . "Nucleotide Transition AbnormalitySYNCI" . . "C0599156"^^ . "Transition Mutation"^^ . "Transition Mutation"^^ . "Transition MutationPTNCI" .