The number of genes differentially expressed between tissues different in FMDV tropism in non-infected animals.

CB: coronary band; DSP: distal soft palate; DSP: distal nasal pharynx; IDC: interdigital cleft skin; LNG: middle anterior lung; MCS: metacarpal skin; NTE: nasal turbinate epithelium; TE: tongue epithelium; NTS: not FMDV targeted sites (MCS, NTE); PIS: persistent infection sites (DNP, DSP); PRS: primary replication sites (DNP, DSP, and LNG); SRS: secondary replication sites (TE, IDC, and CB); -up: up-regulated expression in the tissue group; and -down: down-regulated expression in the tissue group.