NR5A1 (steroidogenic factor 1) is a nuclear receptor transcription factor essential for sexual differentiation and steroidogenic tissue development 1. It functions by binding to specific DNA consensus sequences (5'-YCAAGGYC-3' and 5'-RRAGGTCA-3') in promoter regions of steroidogenic genes including CYP11A, CYP11B, CYP21A, and CYP17, regulating basal and cAMP-dependent transcription 1. NR5A1 also regulates genes controlling anti-Müllerian hormone, adrenal steroidogenesis, and gonadal development. The protein is activated through phosphorylation by HIPK3, enhancing steroidogenic gene expression via cAMP signaling 1. Functionally, NR5A1 interacts with chr9 remodeling complexes and serves as a molecular adapter linking β-catenin to BAF/SWI-SNF machinery for site-specific DNA accessibility 2. NR5A1 mutations cause a spectrum of disorders of sex development (DSD), ranging from 46,XY testicular dysgenesis to 46,XX gonadal dysgenesis 3. Loss-of-function variants are associated with primary ovarian insufficiency, hypogonadism, and male infertility 4. Emerging evidence indicates broader impacts beyond reproduction, including effects on metabolic health and spleen function 5. NR5A1 was the most frequently mutated gene in a male infertility cohort, identified in 12% of patients with spermatogenic failure 6. Clinical phenotypes vary significantly even among carriers of identical mutations, complicating genotype-phenotype correlation 3. Early genetic testing during the neonatal period is recommended when gonadal dysgenesis is suspected.