Editing Chargaff's rules (section)

{{short description|Two rules about the percentage of A, C, G, and T in DNA strands}}
[[File:DNA Diagram.png|thumb|right|upright=1.55|A diagram of DNA base pairing, demonstrating the basis for Chargaff's rules]]
'''Chargaff's rules''' (given by [[Erwin Chargaff]]) state that in the [[DNA]] of any species and any organism, the amount of [[guanine]] should be equal to the amount of [[cytosine]] and the amount of [[adenine]] should be equal to the amount of [[thymine]]. Further, a 1:1 [[Stoichiometry|stoichiometric]] ratio of [[purine]] and [[pyrimidine]] bases (i.e., <code>A+G=T+C</code>) should exist. This pattern is found in both strands of the DNA. They were discovered by Austrian-born chemist [[Erwin Chargaff]]<ref name="Elson1952">{{cite journal |doi=10.1007/BF02170221 |vauthors=Elson D, Chargaff E |year=1953 |title=On the deoxyribonucleic acid content of sea urchin gametes |journal=Experientia |volume=8 |issue=4 |pages=143–145 |pmid=14945441|s2cid=36803326 }}</ref><ref name="Chargaff1952">{{cite journal |vauthors=Chargaff E, Lipshitz R, Green C |s2cid=11358561 |year=1952 |title=Composition of the deoxypentose nucleic acids of four genera of sea-urchin |journal=J Biol Chem |volume=195 |issue=1 |pages=155–160 |doi=10.1016/S0021-9258(19)50884-5 |pmid=14938364|doi-access=free }}</ref> in the late 1940s.