Introduction: SEMA3E is a secreted class 3 semaphorin that, in mice, plays roles in neuronal guidance, cardiovascular morphogenesis, angiogenesis, and vascular homeostasis. Adult male mice lacking SEMA3E exhibit reduced testicular size compared to wild-type littermates, indicating a potential role in reproductive function. In humans, heterozygous missense variants in SEMA3E were initially reported to be associated with CHARGE syndrome and hypogonadotropic hypogonadism with anosmia. However, these associations have since been questioned, and the contribution of SEMA3E variants to human disease is unclear. METHODS:We describe the results of exome sequencing of a 46,XY boy with unexplained bilateral testicular regression syndrome and optic nerve atrophy. RESULTS:Exome sequencing indicates that he carries a heterozygous frameshift variant (c.942del, p.Leu314PheTer11) in the SEMA3E gene. The variant is located within the functional SEMA domain of the protein and is predicted to trigger nonsense-mediated mRNA decay. This is the second reported loss-of-function (LoF) variant in the highly conserved SEMA3E gene. A previously described LoF variant was identified in a child presenting with severe intellectual disability and cognitive regression. CONCLUSION:LoF SEMA3E variants may be associated with a broad and variable spectrum of clinical phenotypes. .

Recurrent heterozygous missense variants in the highly conserved RNA-helicase DHX37, which is required for ribosome biogenesis, are a frequent cause of 46,XY sex-reversal or testis regression syndrome. How these missense variants specifically disrupt testis formation is unknown. Here, we demonstrate that mutant DHX37 proteins retain their ATPase activity and are not associated with stabilization of cellular beta-catenin. Transfection of DHX37 p.R674Q mutant protein in an in-vitro cellular model recapitulating human Sertoli cell formation, showed a reduced activation of pro-testis genes compared to the WT protein. The expression of a DHX37 mutant protein in in-vitro derived human Sertoli-like cells (iSLCs) was also associated with global changes in gene expression, predicted to impact basic cellular functions. To define RNA transcripts interacting with either the WT or a mutant (p.R674Q) protein, we combined HyperTRIBE and single-cell full-length RNA-sequencing approaches using iSLCs. Gene ontology analysis indicated that transcripts targeted by WT DHX37 were primarily associated with cytoskeleton organization, including cell motility and cell adhesion. However, in contrast transcripts targeted by the mutated DHX37 protein, were not only associated with cytoskeleton organization but also with protein degradation and cell death. These data provide mechanistic framework that may explain how variants in the DHX37 protein can result in 46,XY sex-reversal through altered RNA networks that are required for the formation and maintenance of the supporting cell lineages of the human testis. ### Competing Interest Statement The authors have declared no competing interest.

Primary ovarian insufficiency (POI) is characterized by the loss of normal ovarian function and depletion of the ovarian reserve before the age of 40. Approximately 4–30

BACKGROUND:Endocrine science remains underrepresented in European Union research programs despite the fundamental role of hormone health in human wellbeing. Analysis of the CORDIS database reveals a persistent gap between the societal impact of endocrine disorders and their research prioritization. At national funding level, endocrine societies report limited or little attention of national research funding towards endocrinology. The EndoCompass project-a joint initiative between the European Society of Endocrinology and the European Society of Paediatric Endocrinology, aimed to identify and promote strategic research priorities in endocrine science to address critical hormone-related health challenges. METHODS:Research priorities were established through comprehensive analysis of the EU CORDIS database covering the Horizon 2020 framework period (2014-2020). Expert consultation was conducted to identify key research priorities, followed by broader stakeholder engagement including society members and patient advocacy groups. RESULTS:Research priorities encompass variations in sex development, hypothalamic-pituitary-gonadal regulation, and female and male reproductive disorders. Key areas include improving diagnostic capacity through (epi)genetic analysis, optimizing hormonal treatments, developing fertility preservation strategies. Special emphasis is placed on establishing pan-European registries, developing novel reproductive technologies, and exploring environmental impacts on reproductive health. CONCLUSIONS:This component of the EndoCompass project provides an evidence-based roadmap for strategic research investment. This framework identifies crucial investigation areas into reproductive and developmental endocrinology pathophysiology, prevention, and treatment strategies, ultimately aimed at reducing the burden of these disorders on individuals and society. The findings support the broader EndoCompass objective of aligning research funding with areas of the highest potential impact in endocrine health.

INTRODUCTION:Teratozoospermia, characterized by abnormal sperm morphology, is a significant factor contributing to the male infertility. Deubiquitinating enzymes play a crucial role in controlling protein synthesis and degradation during spermatogenesis. METHODS:Whole exome sequencing (WES) and the following insilico analysis were performed to detect the associated variant with asthenoteratozoospermia in a consanguineous Iranian family with two affected brothers. RESULTS:WES identified a novel candidate hemizygous missense mutation (chrX-132161044 T > G:NM_031907.2:c.1205A > C, p.Asn402Thr) in the catalytic domain of the USP26 (Ubiquitin-Specific Peptidase 26) deubiquitinating enzyme in two affected siblings. The USP26 encodes a testis-specific deubiquitinating enzyme which is necessary for normal spermatogenesis and may influence male fertility. The mutation changes asparagine 402 (N) into threonine (T) and was co-segregated with phenotype in other available family members. In-silico predictions indicate that the N402T change not only leads to the absence of a hydrogen bond between the mutant N402T and F430 residues but also causes a reduction in USP26 protein stability, potentially resulting in defects in USP26 enzymatic activity. CONCLUSIONS:Our findings support a potential role for USP26 variants contributing to asthenoteratozoospermia.

Differences of sex development (DSD) refer to various congenital conditions affecting the urogenital and hormonal systems. Accurate diagnosis and personalized management are crucial for supporting patients through complex decisions, such as those related to gender identity. This study represents the first comprehensive investigation into DSD in Iran, analyzing patient’s clinical and genetic data between 1991 and 2020. Karyotype analysis was performed on 69 patients without a molecular diagnosis, with sex chromosome DSD excluded. Presence of SRY gene evaluated in all sex reversal patients. Whole exome sequencing (WES) was used for 26 undiagnosed patients, revealing pathogenic variants in WT1 , NR5A1 , DHX37 , AR , CYP17A1 , and LHCGR genes. The most common diagnosis was testicular TDSD, identified in 42 patients (60.86 %), with the SRY gene being the primary cause in 36 of these patients. The study highlights the importance of genetic analysis in identifying novel and rare gene variants, particularly within the steroid hormone and gonad differentiation pathways, for both 46, XY and 46, XX DSD. These findings emphasize the need for genetic analysis in providing personalized patient care and tailored counseling to help individuals navigate complex decisions, including those involving gender identity.

The Y-linked SRY gene initiates mammalian testis-determination. However, how the expression of SRY is regulated remains elusive. Here, we demonstrate that a conserved steroidogenic factor-1 (SF-1)/NR5A1 binding enhancer is required for appropriate SRY expression to initiate testis-determination in humans. Comparative sequence analysis of SRY 5' regions in mammals identified an evolutionary conserved SF-1/NR5A1-binding motif within a 250 bp region of open chromatin located 5 kilobases upstream of the SRY transcription start site. Genomic analysis of 46,XY individuals with disrupted testis-determination, including a large multigenerational family, identified unique single-base substitutions of highly conserved residues within the SF-1/NR5A1-binding element. In silico modelling and in vitro assays demonstrate the enhancer properties of the NR5A1 motif. Deletion of this hemizygous element by genome-editing, in a novel in vitro cellular model recapitulating human Sertoli cell formation, resulted in a significant reduction in expression of SRY. Therefore, human NR5A1 acts as a regulatory switch between testis and ovary development by upregulating SRY expression, a role that may predate the eutherian radiation. We show that disruption of an enhancer can phenocopy variants in the coding regions of SRY that cause human testis dysgenesis. Since disease causing variants in enhancers are currently rare, the regulation of gene expression in testis-determination offers a paradigm to define enhancer activity in a key developmental process.

NR2F2 encodes COUP-TFII, an orphan nuclear receptor involved in mammalian gonadogenesis. COUP-TFII is expressed in the interstitial/stromal compartment of both fetal testes and ovaries, where it is required for developing steroidogenic lineages. Pathogenic variants in human NR2F2 are linked to testis formation in 46,XX individuals (46,XX disorders of sex development, 46,XX DSD). Such findings propose a regulatory role of COUP-TFII in the developing ovary, whereas its function in testis remains unknown. We evaluate the effect of a de novo heterozygous, predicted damaging, missense variant in NR2F2 (p.Arg246His) in a 46,XY under-masculinized boy. In-vitro assays show that the mutant protein significantly loses the inhibitory effect on NR5A1-mediated activation of both the LHB and INSL3 promoters. The data support the pathogenicity of the p.Arg246His variant in 46,XY DSD and a role for NR2F2 in human testis formation. In addition to NR5A1 and WT1 , NR2F2 variants are thus associated with both 46,XX and 46,XY DSD. This expands the list of genes that function in both male and female sex development, which is originally thought to be regulated by two entirely different sets of genes. ### Competing Interest Statement The authors have declared no competing interest.

NR2F2 encodes COUP-TFII, an orphan nuclear receptor required for the development of the steroidogenic lineages of the murine fetal testes and ovaries. Pathogenic variants in human NR2F2 are associated with testis formation in 46,XX individuals, however, the function of COUP-TFII in the human testis is unknown. We report a de novo heterozygous variant in NR2F2 (c.737G > A, p.Arg246His) in a 46,XY under-masculinized boy with primary hypogonadism. The variant, located within the ligand-binding domain, is predicted to be highly damaging. In vitro studies indicated that the mutation does not impact the stability or subcellular localization of the protein. NR5A1, a related nuclear receptor that is a key factor in gonad formation and function, is known to physically interact with COUP-TFII to regulate gene expression. The mutant protein did not affect the physical interaction with NR5A1. However, in-vitro assays demonstrated that the mutant protein significantly loses the inhibitory effect on NR5A1-mediated activation of both the LHB and INSL3 promoters. The data support a role for COUP-TFII in human testis formation. Although mutually antagonistic sets of genes are known to regulate testis and ovarian pathways, we extend the list of genes, that together with NR5A1 and WT1, are associated with both 46,XX and 46,XY DSD.