Epigenetic control of SOX9 gene by the histone acetyltransferase P300 in human Sertoli cells.

Background: The transcription factor SOX9 is a key regulator of male sexual development and Sertoli cell differentiation. Altered SOX9 expression has been implicated in the pathogenesis of disorders of sexual development (DSD) in mammals. However, limited information exists regarding the epigenetic mechanisms governing its transcriptional control during sexual development. Methods: This study employed real-time PCR (qPCR), immunofluorescence (IIF), and chromatin immunoprecipitation (ChIP) assays to investigate the epigenetic mechanisms associated with SOX9 gene transcriptional control in human and mouse Sertoli cell lines. To identify the specific epigenetic enzymes involved in SOX9 epigenetic control, functional assays using siRNAs for P300, GCN5, and WDR5 were performed. Results: The transcriptional activation of SOX9 was associated with selective deposition of active histone modifications, such as H3K4me3 and H3K27ac, at its enhancer and promoter regions. Importantly, the histone acetyltransferase P300 was found to be significantly enriched at the SOX9 enhancers, co-localizing with the H3K27ac and the SOX9 transcription factor. Silencing of P300 led to decreased SOX9 expression and reduced H3K27ac levels at the eSR-A and e-ALDI enhancers, demonstrating the crucial role of P300-mediated histone acetylation in SOX9 transcriptional activation. Interestingly, another histone lysine acetyltransferases like GNC5 and methyltransferases as the Trithorax/COMPASS-like may also have a relevant role in male sexual differentiation. Conclusions: Histone acetylation by P300 at SOX9 enhancers, is a key mechanism governing the transcriptional control of this essential regulator of male sexual development. These findings provide important insights into the epigenetic basis of sexual differentiation and the potential pathogenesis of DSDs.

Cytogenomic Investigation of Syndromic Brazilian Patients with Differences of Sexual Development.

BACKGROUND: Cytogenomic methods have gained space in the clinical investigation of patients with disorders/differences in sexual development (DSD). Here we evaluated the role of the SNP array in achieving a molecular diagnosis in Brazilian patients with syndromic DSD of unknown etiology. METHODS: Twenty-two patients with DSD and syndromic features were included in the study and underwent SNP-array analysis. RESULTS: In two patients, the diagnosis of 46,XX SRY + DSD was established. Additionally, two deletions were revealed (3q29 and Xp22.33), justifying the syndromic phenotype in these patients. Two pathogenic CNVs, a 10q25.3-q26.2 and a 13q33.1 deletion encompassing the FGFR2 and the EFNB2 gene, were associated with genital atypia and syndromic characteristics in two patients with 46,XY DSD. In a third 46,XY DSD patient, we identified a duplication in the 14q11.2-q12 region of 6.5 Mb associated with a deletion in the 21p11.2-q21.3 region of 12.7 Mb. In a 46,XY DSD patient with delayed neuropsychomotor development and congenital cataracts, a 12 Kb deletion on chromosome 10 was found, partially clarifying the syndromic phenotype, but not the genital atypia. CONCLUSIONS: The SNP array is a useful tool for DSD patients, identifying the molecular etiology in 40% (2/5) of patients with 46,XX DSD and 17.6% (3/17) of patients with 46,XY DSD.

The Molecular Basis of 5α-Reductase Type 2 Deficiency.

The 5α-reductase type 2 enzyme catalyzes the conversion of testosterone into dihydrotestosterone, playing a crucial role in male development. This enzyme is encoded by the SRD5A2 gene, which maps to chromosome 2 (2p23), consists of 5 exons and 4 introns, and encodes a 254 amino acid protein. Disruptions in this gene are the molecular etiology of a subgroup of differences of sex development (DSD) in 46,XY patients. Affected individuals present a large range of external genitalia undervirilization, ranging from almost typically female external genitalia to predominantly typically male external genitalia with minimal undervirilization, including isolated micropenis. This is an updated review of the implication of the SRD5A2 gene in 5α-reductase type 2 enzyme deficiency. For that, we identified 451 cases from 48 countries of this particular 46,XY DSD from the literature with reported variants in the SRD5A2 gene. Herein, we present the SRD5A2 mutational profile, the SRD5A2 polymorphisms, and the functional studies related to SRD5A2 variants to detail the molecular etiology of this condition.

Fetal Genotype-Phenotype Sex Discordance: A Case of 5-Alpha-Reductase Deficiency.

OBJECTIVE: To describe the prenatal and postnatal diagnostic workup leading to the diagnosis of 5-alpha-reductase type 2 deficiency (5AR2D) in a case of 46,XY disorder of sex development (DSD). CASE REPORT: A first-trimester noninvasive prenatal test (NIPT) on maternal blood revealed a male fetus with a low risk of aneuploidy. However, a female fetus was identified at the second-trimester scan. A repeat sample revealed similar results and ruled out the possibility of both a sample swap or a vanishing twin. At birth, phenotypically female external genitalia were evident, with testes noted in the labioscrotal area. Neonatal blood confirmed a 46,XY complement and a 46,XY DSD genetic panel revealed a 5AR2D. CONCLUSION: Our case and others described in the literature demonstrate that fetal sex discordance detected by a combination of NIPT and subsequent ultrasound examination can be associated with several biological conditions, with DSD being the most significant.

Are NR5A1 Variations a Frequent Cause of 46,XX Ovotesticular Disorders of Sex Development? Analysis from a Single Center and Systematic Review.

INTRODUCTION: Ovotesticular disorder of sex development (OT-DSD) is a rare condition defined by concomitance of testicular tissue and ovarian tissue (containing follicles) in the same individual. In SRY-negative 46,XX OT-DSD, the presence of testicular tissue may be due to variations in NR5A1. Our aims were to search for NR5A1 variants in SRY-negative 46,XX OT-DSD patients and to perform a systematic review on the contribution of NR5A1 variations to 46,XX OT-DSD. METHODS: Sanger sequencing of NR5A1 was performed in seven SRY-negative 46,XX OT-DSD patients: five simplex cases and two with another sibling with a 46,XX DSD. Systematic review of original studies on NR5A1 sequencing of 46,XX OT-DSD patients was performed according to PRISMA-P guideline. Case reports were selected for analysis of clinical features. Individuals with NR5A1-associated testicular DSD were not included. RESULTS: Sanger sequencing of NR5A1 did not reveal pathogenic variants among our patients. Our cohort was included in this systematic review with seven other articles, totalizing fifty-six 46,XX OT-DSD patients investigated by Sanger or whole-exome sequencing. From them, three NR5A1 pathogenic variants were identified (5% of the cases). Clinical analysis of these 3 cases and 5 case reports revealed: predominance of ovotestis (13/16 gonads) and bilateral OT-DSD (5/8 cases). CONCLUSION: The etiology of most 46,XX OT-DSD cases remains elusive, highlighting the importance of a deeper molecular investigation.

Disorders of Sexual Development: Current Status and Progress in the Diagnostic Approach.

Disorders of sexual development (DSD) are conditions with an atypical chromosomal, gonadal or phenotypic sex, which leads to differences in the development of the urogenital tract and different clinical phenotypes. Some genes have been implicated in the sex development during gonadal and functional differentiation where the maintenance of the somatic sex of the gonad as either male or female is achieved by suppression of the alternate route. The diagnosis of DSD requires a structured approach, involving a multidisciplinary team and different molecular techniques. We discuss the dimorphic genes and the specific pathways involved in gonadal differentiation, as well as new techniques for genetic analysis and their diagnostic value including epigenetic mechanisms, expanding the evidence in the diagnostic approach of individuals with DSD to increase knowledge of the etiology.

Trastornos de diferenciación sexual

Objetivo: Presentar la clínica, citogenética y hallazgos histopatológicos en pacientes adultas, que consultaron a la Unidad de Endocrinología Ginecológica del Hospital Universitario de Caracas con trastornos de la diferenciación sexual. Se reportan cuatro casos clínicos: dos casos con trastorno de la diferenciación sexual 46, XY por alteración en la acción de los andrógenos anteriormente denominado insensibilidad androgénica parcial, una paciente con trastorno de la diferenciación sexual 46, XX y otra con trastorno de la diferenciación sexual 46, XY ovotesticular sin gonadoblastoma por síndrome de Frasier. Es importante realizar un diagnóstico temprano para su tratamiento precoz, por la trascendencia que la definición del sexo tiene para el futuro del individuo. Conclusiones: A pesar de los avances alcanzados a lo largo de los últimos 20 años, algunos casos quedan aún sin diagnóstico etiológico definido, sea por falta de estudio molecular o genes aún no conocidos. Su abordaje diagnóstico y terapéutico es complejo, requiere de un equipo multidiscplinario integrado por ginecólogos, endocrinólogos, psiquiatras, urólogos, cirujanos plásticos.

The aim of this paper is to present the clinical, cytogenetic and histopathological findings in adult patients who consulted the Gynecological Endocrinology Unit of the University Hospital of Caracas with Disorders of sexual development. Four clinical cases reported: Two with Disorder of sexual development 46, XY due defect in androgen action previously called partial androgen insensitivity, one patient with disorders of sexual development 46, XX and another with disorder of sexual development 46, XY ovotesticular without gonadoblastoma by Frasier syndrome. It is important an early diagnosis and treatment to define the sex for the individual’s future. Conclusion: Despite the progress made over the last 20 years, some cases are still without etiologic diagnosis, either through lack of molecular study or yet unknown genes. Its diagnostic and therapeutic approach is complex, requiring a team of gynecologists, endocrinologists, psychiatrists, urologists, plastic surgeons.