In our young-onset sporadic PitNET cohort, 6.8% had an AIP mutation, with slightly higher rates in the sporadic somatotropinoma subgroup (10.5%); this is at the level of usual risk recommendation for genetic testing, but we identified low rates in sporadic prolactinomas (1.5%) with no cases of NF-PitNETs or corticotropinomas. This evidence concerns the gene AIP and prolactin-producing pituitary gland adenoma.