What does paralogy mean?
Paralogy is chiefly a technical term in evolutionary biology for the relationship between genes, proteins, or other biological sequences that became distinct after a common ancestral sequence was duplicated. The process is an important source of biological novelty, because one copy can retain its original function while the other evolves a different role. Paralogy is also used more rarely in linguistics for the relationship between words that resemble one another in form or meaning because they share a historical source. The word should not be confused with analogy, which describes a broad similarity or comparison without necessarily implying shared ancestry. In scientific writing, paralogy usually refers specifically to duplication and subsequent divergence, rather than to a relationship based only on functional resemblance.
nounIn genetics, the evolutionary relationship between genes or other biological sequences that arose through duplication of a common ancestral sequence. More broadly and rarely, it denotes the relationship between words that resemble one another in form or meaning because of a common origin.
- The evolutionary relationship between homologous genes, proteins, or other biological sequences whose divergence followed duplication of a common ancestral sequence.
- The relationship between words in the same language that resemble one another in form or meaning because they share an origin.
"Genomic duplication gave rise to the paralogy between the two genes."
"The researchers used sequence comparison to identify paralogy between the duplicated genes."
"The similarity between 'finesse' and 'finance' is an example of word paralogy."
The regular plural is rare and is chiefly used when several relationships of this kind are being discussed.
"These paralogies provide evidence of repeated gene duplication."
In genetics, paralogy preserves the hidden history of a genome's duplications: two similar genes can be living records of an ancient copying accident.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of paralogy
Paralogy was formed from Greek para, meaning 'beside,' combined with -logy, a term associated with the study or systematic account of something. The terminology reflects the idea of placing biological sequences beside one another for comparison. Its relatives include parallel and the biological adjective paralogous, which describes sequences related through duplication rather than direct functional equivalence.
Related word forms
How paralogy is actually used
This is a specialized and comparatively uncommon term. In biology it is usually restricted to relationships arising through gene or genomic duplication, while its older linguistic use concerns related or historically similar words.
Easily confused with paralogy
Paralogy specifically concerns sequences or words connected through shared ancestry, whereas analogy is a general similarity or comparison between two things.