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One of the organic bases found in DNA and RNA. Cytosine pairs with base guanine and is denoted by the letter ‘C’.

Use in clinical context

The pairing of bases allows DNA to accurately replicate itself and to be transcribed into RNA. The order of bases in a gene determines the order of amino acids in a protein. Changes to the bases can result in changes to the amino acids and the resulting protein function. Determining the order of bases is the aim of sequencing as this can then be used to identify any functional change in the DNA.

Last updated on 3rd June, 2019