Runtime Error in component "EnsEMBL::Web::Component::Gene::Summary [content]"
Function EnsEMBL::Web::Component::Gene::Summary fails to execute due to the following error:
Can't call method "display_xref" on an undefined value at ... /nfs/public/release/ensweb/live/www/www_111/ensembl-webcode/modules/EnsEMBL/Web/Component/Summary.pm line ... 199.