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​Cytosine

updated: August 10, 2022

Definition

Cytosine (C) is one of the four nucleotide bases in DNA, with the other three being adenine (A), guanine (G) and thymine (T). Within a double-stranded DNA molecule, cytosine bases on one strand pair with guanine bases on the opposite strand. The sequence of the four nucleotide bases encodes DNA’s information.

 Cytosine


Narration

Cytosine. The fact that DNA encodes all of its information in four bases, each with its own letter, allows us to write the DNA code by just representing the letters.

Lawrence Brody
Lawrence Brody, Ph.D.

Director

Division of Genomics and Society