Linked from
The 6 pages that link to Uracil, each with the reason it gives.
AdenineCompared with: Uracil takes thymine’s pairing role opposite adenine in RNA.
GuanineCompared with: Uracil occupies RNA's adenine-pairing role, unlike guanine's pairing role.
PyrimidineBroader topic: Uracil occupies the corresponding position to thymine in RNA.
ThymineCompared with: RNA usually uses uracil where DNA uses thymine.
UridineRelated: Uracil is the base joined to ribose to form uridine.