Results revealed that most patients taking prolactin-inducing antipsychotics had osteoporosis and stage IV (severe) periodontitis, while in those taking prolactin-sparing antipsychotics, osteopenia and stage III (less severe) periodontitis were most prevalent, whereas the majority of newly diagnosed patients had normal bone with stage I or II (initial or moderate) periodontitis. The gene discussed is PRL; the disease is osteoporosis.