It is interesting to note that, for the high-PRL group, levels of FSH and LH were decreased and levels of oestrogen also showed a significant decrease, supporting the hypothesis that high-PRL levels inhibit the hypothalamic-pituitary-gonadal axis and thus that antipsychotic medication may play a role in the development of osteoporosis in patients with schizophrenia. This evidence concerns the gene PRL and schizophrenia.