The adrenal cortex produces essential steroid hormones through a concentric zonal architecture, established by the centripetal transdifferentiation of subcapsular progenitors within a capsule-derived niche. To capture this complexity, we establish a human pluripotent stem cell-derived adrenal organoid system that faithfully recapitulates this process. RSPO3/WNT signaling from the capsule specifies definitive zone (DZ) progenitors from the adrenal primordium, which then differentiate into a cortisol-producing transitional zone and an androgen-producing fetal zone under the influence of RSPO3 and ACTH. Loss of NR0B1 impairs DZ specification and triggers direct adrenal primordium-to-fetal zone conversion, mirroring the mechanism of X-linked adrenal hypoplasia congenita. When DZ cells are encapsulated with capsule cells separately derived from pluripotent stem cells, they reconstitute zonation in vivo, forming ACTH-responsive tissue that produces both cortisol and androgens. This organoid platform offers a powerful tool to dissect human adrenal development and establishes a foundation for regenerative therapies targeting adrenal diseases.

X-linked adrenal hypoplasia congenita (AHC) is a rare, life-threatening disorder caused by pathogenic variants in NR0B1 (DAX1), leading to adrenal insufficiency and hypogonadotropic hypogonadism. AHC is often associated with Xp21 contiguous gene deletion syndrome, which involves the deletion of multiple genes, including NR0B1, GK, DMD, and IL1RAPL1, resulting in a spectrum of phenotypic manifestations, such as glycerol kinase deficiency (GKD), Duchenne muscular dystrophy (DMD), and neurodevelopmental disorders. We report two cases of AHC with neurodevelopmental delays due to contiguous Xp21 deletions involving NR0B1 and IL1RAPL1, each diagnosed through distinct clinical pathways. Case 1 involved a neonate with adrenal insufficiency, persistent hyperCKemia, and excessive urinary glycerol excretion, leading to a diagnosis of Xp21 deletion syndrome with DMD and GKD. The patient's sister, an asymptomatic carrier, exhibited elevated CK levels and mild developmental delays. Array comparative genomic hybridization identified a novel complex structural variation, including duplication-deletion-duplication rearrangement, which may have modified clinical manifestations. Case 2 involved a 10-year-old boy with AHC and developmental delay that was initially considered a consequence of adrenal crises. Genetic analysis confirmed an Xp21 deletion, including IL1RAPL1, implicating it in his intellectual disability. A literature review reveals that Xp21 deletions involving IL1RAPL1 are strongly associated with neurodevelopmental delays, suggesting a distinct phenotype within Xp21 deletion syndromes. Early genetic diagnosis via chromosomal microarray analysis facilitates precise delineation of deletion regions, aiding in clinical management, genetic counseling, and early intervention strategies. Further studies are needed to elucidate genotype-phenotype correlations in Xp21 deletion syndromes and optimize individualized medical care.

NR0B1 (DAX-1) is an orphan nuclear receptor essential for the development and regulation of the adrenal glands and gonads. Pathogenic variants in NR0B1 cause X-linked adrenal hypoplasia congenita (AHC), which typically presents with adrenal insufficiency and hypogonadotropic hypogonadism (HH) in boys. Delayed diagnosis during adolescence is uncommon but, when it occurs, can lead to preventable adrenal crisis, underscoring the need for early recognition of atypical presentations. We describe a 14-year-old boy who presented with adrenal insufficiency and delayed puberty. Genetic testing revealed a novel hemizygous in-frame duplication variant of NR0B1 (NM_000475.4:c.833_835dup p.(Leu278dup)). This variant has not been previously reported in association with X-linked AHC. The patient received hydrocortisone (10-12 mg/m2/day) and fludrocortisone (0.1 mg/day) as replacement therapy for adrenal insufficiency, along with testosterone supplementation (100-240 mg/day) to induce pubertal progression. Plasma ACTH levels gradually decreased from 10,175 pg/mL at diagnosis to 215 pg/mL during follow-up, accompanied by clinical improvement in skin pigmentation and pubertal development. This case underscores the importance of NR0B1 genetic testing in children with adrenal insufficiency and HH. Early recognition and genetic confirmation are critical for appropriate management and genetic counseling. Identification of novel variants expands the NR0B1 mutational spectrum and enhances our understanding of genotype-phenotype correlations in X-linked AHC.

X-linked adrenal hypoplasia congenita (X-AHC) is a hereditary disease caused by pathogenic NR0B1 variants which result in primary adrenal insufficiency and hypogonadotropic hypogonadism. We report four male patients diagnosed with X-AHC from three maternally-related families. Genetic testing used next-generation sequencing (Cases 1 and 3) or Sanger sequencing (Cases 2 and 4). All patients harbored a novel pathogenic variant of the NR0B1 gene (c.94_113del, p.Thr32Leufs*). Cases 1 and 2 displayed acute onset neonatal congenital adrenal insufficiency and had hypogonadotropic hypogonadism. In contrast, cases 3 and 4 experienced delayed adrenal insufficiency and demonstrated normal pubertal development. Although pubertal development in X-AHC is diverse, reports of normal pubertal development are scarce. We report a novel NR0B1 variant with diverse manifestations.

The adrenal cortex produces essential steroid hormones through a concentric zonal architecture, established by the centripetal trans-differentiation of subcapsular progenitors within a capsule-derived niche. To capture this complexity, we establish a human pluripotent stem cell-derived adrenal organoid system that faithfully recapitulates this process. RSPO3/WNT signaling from the capsule specifies definitive zone (DZ) progenitors from the adrenal primordium, which then differentiate into a cortisol-producing transitional zone and an androgen-producing fetal zone under the influence of RSPO3 and ACTH. Loss of NR0B1 impairs DZ specification and triggers direct adrenal primordium-to-fetal zone conversion, mirroring the mechanism of X-linked adrenal hypoplasia congenita. When DZ cells are encapsulated with capsule cells separately derived from pluripotent stem cells, they reconstitute zonation in vivo, forming ACTH-responsive tissue that produces both cortisol and androgens. This organoid platform offers a powerful tool to dissect human adrenal development and establishes a foundation for regenerative therapies targeting adrenal diseases.