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To the Editor, Septo-optic dysplasia (SOD) is an uncommon congenital disorder characterized by a classical triad of optic nerve hypoplasia, midline brain malformations, and hypothalamic–pituitary dysfunction[1]. Despite its heterogeneous etiopathogenesis, pathogenic variants in the HESX1 gene, a homeobox-containing transcription factor essential for forebrain and pituitary development have been implicated in a subset of familial and sporadic cases[2]. Notably, HESX1 haploinsufficiency may result in paradoxical endocrine phenotypes, including endocrine precocity rather than the expected hypopituitarism[3]. With advances in precision gene–regulatory technologies, CRISPR interference (CRISPRi) has emerged as a promising approach for modulating dosage-sensitive genes, offering a potential strategy to normalize early neuroendocrine signaling in HESX1-related SOD[4,5]. CRISPRi takes advantage of a catalytically inactive version of Cas9 (dCas9) conjugated to transcriptional repressor modules, and thus provides a safety benefit in the context of SOD, where an overexpression or unsuitable repression of developmental pathways may worsen central nervous system or endocrine disease. Transcriptional dysregulation associated with HESX1 haploinsufficiency may disrupt the homeostatic control of key developmental signaling pathways, including Wnt and Notch, which are tightly linked to early pituitary morphogenesis[6]. Developmental homeostasis reinstallation and normalizing pituitary–hypothalamic function may be achieved through CRISPRi-mediated suppression of aberrant pathway activation. Of particular interest is that endocrine precocity is an uncommon presentation in patients with HESX1 mutations. The mechanisms proposed for this rare phenotype include disturbances in hypothalamic regulatory pathways, ectopic activation of gonadotropin-releasing hormone (GnRH) neurons, and altered feedback resulting from midline brain defects[7]. Currently, no gene-based therapy exists to correct these mechanistic derangements. However, CRISPRi could offer a solution to silencing the pathogen. The initial in vitro experiments indicate that CRISPRi has the potential to adjust the transcriptional networks of neuroendocrine signaling and, thus, its usefulness in these clinical conditions is conceptually justified[8]. Despite its therapeutic potential, CRISPRi faces significant obstacles before it can be translated into a viable clinical therapy for SOD. HESX1 mutations are rare and heterogeneous, complicating the development of universal delivery constructs. In addition, the practical and precise targeting of the emerging central nervous system, be it through the AAV in the form of dCas9 or nanoparticle-based vectors, must undergo considerable refinement to ensure specific functionality and reduce the number of long-term off-target silencing. Ethical considerations are equally relevant; any manipulation of early developmental gene regulatory networks requires serious consideration to ensure that specific activity is obtained and long-term off-target silencing is minimized. Still, CRISPRi is at the center of a paradigm shift in cases of congenital endocrine and neurodevelopmental disorders treatment. Its non-mutagenic tunable transcriptional dampening makes it highly adapted to pathologies that occur due to dosage imbalance and not structural gene lesions. Additional studies that use the system of patient-derived induced pluripotent stem cells and human hypothalamic–pituitary organoid models would clarify the ability of CRISPRi to correct the molecular impairments of HESX1 haploinsufficiency. It is urgent to mobilize the scientific community in favor of the translational research on the use of CRISPRi in rare developmental diseases. In conditions previously considered molecularly inaccessible to therapeutic intervention, such as SOD, precision gene modulation may represent a novel and potentially transformative therapeutic strategy. Ethical approval Not applicable. Consent Not applicable.