[GodGunsGuts]

Can either of you tell me the difference between evolutionarily conserved and evolutionarily constrained?

[allmendream]

Evolutionary constraint means that a hemoglobin protein has to bind oxygen and do its job. Their is an absolute limit to how ‘different’ the protein can change. Most sequences of absolute evolutionary constraint are at the active domains of a protein; where the action is, where it is binding something, or catalyzing, or being phosphorylated.

Evolutionary conservation means that a sequence is more highly conserved between closely related species than other sequences that do not show evolutionary conservation. Genes and regulatory sequences show the highest evolutionary conservation. Most ERV’s and pseudogenes and repeat sequences show the lowest evolutionary conservation.

It is thought that things that show low evolutionary conservation, are thus not under any evolutionary constraint, because they have no essential function, and can be changed without any ill effect.