Estrogen [9], bisphosphonates [10] or parathyroid hormone (PTH) [11] have been used to prevent postmenopausal alveolar bone loss, but many lines of evidence indicate that long-term treatments with those drugs might cause adverse reactions, such as an increased risk of ovarian and endometrial cancer [12,13], osteonecrosis of the jaws [14], nervous system disorders [15] and venous thromboembolism [16]. The gene discussed is PTH; the disease is nervous system disorder.