EspaƱol
Questions About Cancer? 1-800-4-CANCER
  • Print
  • Facebook
  • Twitter
  • Google+
  • Pinterest

NCI Dictionary of Cancer Terms


cytosine  listen  (SY-toh-seen)

  A chemical compound that is used to make one of the building blocks of DNA and RNA. It is a type of pyrimidine.

Enlarge
Structure of DNA; drawing shows a chromosome, nucleosome, histone, gene, and nucleotide base pairs: guanine, cytosine, adenine, and thymine. Also shown is a cell and its nucleus.