Gene mutations contributing to disordered pituitary development can themselves be classified: mutations affecting transcriptional determinants of pituitary development, mutations related to gonadotropin deficiency, mutations concerning the beta subunit of FSH and LH, and mutations in the DAX-1 gene as a cause of adrenal hypoplasia and disturbed responsiveness of the pituitary to GnRH. This evidence concerns the gene BRD2 and chronic primary adrenal insufficiency.