This intriguing result points to a novel role for the brain NHLH2 transcription factor in testicular cells and raises the interesting possibility that curative hormone therapy not only influences gene expression in the testis, but in the central nervous system (CNS) as well, as NHLH2’s role in the brain is known to be critical for hypogonadotropic hypogonadism. The gene discussed is NHLH2; the disease is hypogonadotropic hypogonadism.