Testicular function in men with FXS is not mediated by hormones (LH, FSH, testosterone, dihydrotestosterone, androstenedione, 17-hydroxyprogesterone, progesterone, dehydroepiandrosterone and dehydroepiandrosterone-sulfate) [30], but considering the dearth of literature regarding hormone levels in FXS patients and the strong macroorchidism phenotype, the dysregulation of PRL may be a viable biomarker and therapeutic target. Here, PRL is linked to fragile X syndrome.