Mutual information and direct coupling analysis reveal residue contacts
Coevolving residue pairs in a protein family reveal structural contacts: if positions i and j are in contact, mutations at i are compensated by mutations at j to maintain fitness. Mutual information I(i,j) captures this but conflates direct and indirect correlations. Direct Coupling Analysis (DCA, Weigt et al 2009) uses a Potts model to disentangle direct from transitive couplings.