Phylogenetic profile of homologous proteins families (HPF) known to be involved in structural functions (capsid, tegument, virus assembly). The presence of the family in any genome is indicated by 1 and the absence by 0. Alpha, Alphaherpesviruses; Beta, Betaherpesviruses; and Gamma, Gammaherpesviruses. The HPF numbers are indicated and relate directly to accompanying data available athttp://www.biochem.ucl.ac.uk/bsm/virus_database. HPF 1^* is indicated twice because it represents a shared domain present in both the major and minor capsid proteins of all herpesviruses.