The discriminative genes selected through CFS are GI_10092618-S-4, GI_10835022-S-8, GI_37059795-S-1, GI_37059795-S-5, GI_46255021-A-6, GI_51477209-S-8, GI_53729348-S-2, GI_56119169-S-5, GI_71773149-A-8, GI_9945331-S-4 (NFKBIA, ITPR1, MGC26963, MGC26963, ERG, BEXL1, PLAU, CCL2, APRT, and GADD45B, respectively). The gene discussed is APRT; the disease is myalgic encephalomeyelitis/chronic fatigue syndrome.