PMAIP1 and osteoporosis: After the non-SDEGs added by GeneMANIA to establish the PPI network removed, six up-regulated SDEGs (HIST1H3G, HIST1H2BO, PTP4A1, FAM46A, MT1G and TNFSF9) and one down-regulated SDEG (PMAIP1) were identified as potential hub genes in the pathogenesis of osteoporosis.