Horse performance gene–transcription factor (TF) network, focus 1. Rounded square nodes represent the TFs, wherein four main TFs are highlighted: EGR1, TFAP2A, SP1, and ARNT. Yellow nodes are associated with three or more groups, while those with two colors (interior and border) represent 2 groups, and nodes with one color represent only one group*. Red diamond nodes are the TF-related biological processes. Gray nodes are the identified candidate genes, whereas the main candidate genes related with horse performance are represented by light pink color. *Green nodes: group 1, purple nodes: group 2; salmon nodes: group 3; blue nodes: group 5; orange nodes: group 7; light green nodes: group 9.