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​Uracil

updated: March 27, 2024

Definition

Uracil (U) is one of the four nucleotide bases in RNA, with the other three being adenine (A), cytosine (C) and guanine (G). In RNA, uracil pairs with adenine. In a DNA molecule, the nucleotide thymine (T) is used in place of uracil.

 Uracil


Narration

Uracil. The fact that uracil is present in RNA and not DNA contributes to the ability of RNA to be degraded easily. This allows the cell to change which genes are being expressed, as the older RNAs do not stick around for very long.

Lawrence Brody
Lawrence Brody, Ph.D.

Director

Division of Genomics and Society