{"term":{"id":"15781","title":"homology","longtitle":"IUPAC Gold Book - homology","doi":"10.1351\/goldbook.15781","code":"15781","status":"current","definitions":[{"id":1,"text":"Similarity of anatomical structures in different species because of shared ancestry\nSimilarity of DNA or RNA nucleotide sequences, or of protein amino-acid sequences, supporting the hypothesis that they share a common ancestor.Note: Homology among DNA or RNA nucleotide sequences, or among protein amino-acid sequences, is often concluded on the basis of sequence similarity. In general, if there are almost identical sequences, it is likely that they are homologous. However, it is possible that highly similar sequences were not derived from a common ancestor, i.e., they are similar but not homologous.","contexts":[],"sources":["PAC, 2007, 79, 1153. 'Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)' on page 1237 (https:\/\/doi.org\/10.1351\/pac200779071153)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/15781\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/15781\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/15781\/plain"},"citation":"Citation: 'homology' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.15781","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-05-10T03:08:17+00:00"}}