Editing GC-content (section)

{{Short description|Percentage of guanine and cytosine in DNA or RNA molecules}}
[[Image:AT-GC.jpg|thumb|400px|Nucleotide bonds showing AT and GC pairs. Arrows point to the [[hydrogen bond]]s.]]
In [[molecular biology]] and [[genetics]], '''GC-content''' (or '''guanine-cytosine content''') is the percentage of [[nitrogenous bases]] in a [[DNA]] or [[RNA]] molecule that are either [[guanine]] (G) or [[cytosine]] (C).<ref>[http://cancerweb.ncl.ac.uk/cgi-bin/omd?GC+content Definition of GC] – content on CancerWeb of [[Newcastle University]], UK</ref> This measure indicates the proportion of G and C bases out of an implied four total bases, also including [[adenine]] and [[thymine]] in DNA and adenine and [[uracil]] in RNA.

GC-content may be given for a certain fragment of DNA or RNA or for an entire [[genome]]. When it refers to a fragment, it may denote the GC-content of an individual [[gene]] or section of a gene (domain), a group of genes or gene clusters, a [[non-coding DNA|non-coding region]], or a synthetic [[oligonucleotide]] such as a [[primer (molecular biology)|primer]].