Median prolactin levels were 93.15 ng/mL, 241.8 ng/mL, 74.5 ng/mL, 93.2 ng/mL, and 69 ng/mL for microadenomas, macroadenomas, idiopathic hyperprolactinemia, drug-induced hyperprolactinemia, and other causes of hyperprolactinemia, respectively. This evidence concerns the gene PRL and hyperprolactinemia.