
CRE sequence conservation patterns per tissue. (A) Weak negative selection inferred from human polymorphisms, separated by the tissue that utilizes the CREs. (B) Fraction of sites under (strong) negative selection, separated by the tissue that utilizes the CREs. (C) Brain CRE sequences were separated into peak and adjacent sequences. (D) The part of the sequence that is used by the brain shows a considerably higher fraction of sites under negative selection than the respective adjacent sequences. (A,B,D) Depicted are mean values ± SEM.











