TNFRSF11B and osteoporosis: In a systematic review, conducted on 14 studies including 2280 healthy controls and 2383 osteoporotic patients, it was reported that the G allele of the OPG A163G variant may increase the risk of osteoporosis in Caucasians, while the C allele of the OPG G1181C variant may reduce the risk of osteoporosis in Asians.