Testicular differentiation in 46,XX DSD: an overview of genetic causes.

In mammals, the development of male or female gonads from fetal bipotential gonads depends on intricate genetic networks. Changes in dosage or temporal expression of sex-determining genes can lead to differences of gonadal development. Two rare conditions are associated with disruptions in ovarian determination, including 46,XX testicular differences in sex development (DSD), in which the 46,XX gonads differentiate into testes, and 46,XX ovotesticular DSD, characterized by the coexistence of ovarian and testicular tissue in the same individual. Several mechanisms have been identified that may contribute to the development of testicular tissue in XX gonads. This includes translocation of SRY to the X chromosome or an autosome. In the absence of SRY, other genes associated with testis development may be overexpressed or there may be a reduction in the activity of pro-ovarian/antitesticular factors. However, it is important to note that a significant number of patients with these DSD conditions have not yet recognized a genetic diagnosis. This finding suggests that there are additional genetic pathways or epigenetic mechanisms that have yet to be identified. The text will provide an overview of the current understanding of the genetic factors contributing to 46,XX DSD, specifically focusing on testicular and ovotesticular DSD conditions. It will summarize the existing knowledge regarding the genetic causes of these differences. Furthermore, it will explore the potential involvement of other factors, such as epigenetic mechanisms, in developing these conditions.

Neovaginoplasty With Nile Tilapia Skin: Cytological and Microbiota Evaluation.

OBJECTIVES: To study the clinical, cytological, and vaginal microbiota findings in patients with Mayer-Rokitansky-Küster-Hauser syndrome who underwent neovaginoplasty using Nile tilapia fish skin. METHODS: This is a cross-sectional study with 7 cisgender women with Mayer-Rokitansky-Küster-Hauser syndrome who had previously undergone neovagina reconstruction using Nile tilapia fish skin at a university hospital. Local institutional review board approval and written permission from the patient were obtained. Between August 2019 and November 2021, within 12 to 24 months after surgery, vaginal specimens were obtained for conventional oncotic and hormonal cytology, and for Gram staining. The Nugent scores were calculated. Colposcopy was also performed. RESULTS: Squamous cells without atypia were found in all patients. Five patients had intermediate vaginal microbiota (Nugent score of 4), which was determined by the presence of few lactobacilli on Gram staining. In hormonal cytology, 4 patients presented with findings compatible with menacme. No colposcopic change was observed. When postsurgical dilation was performed correctly, a mean vaginal length of 8.3 cm was maintained after 1 year of follow-up. CONCLUSIONS: Squamous cells without atypia were present in neovaginas with Nile tilapia fish skin. Most vaginal contents revealed intermediate microbiota and hormonal results compatible with menacme. Studies with a greater number of patients are necessary for a more comprehensive understanding of the microbiome in neovaginas with this new technique, thereby providing support for the treatment and prevention of associated pathologies.

An alternative approach to vaginal dilation in patients with Meyer-Rokitanski-Küster-Hauser syndrome: two case reports.

Vaginal dilation, currently considered as the first-line therapy for vaginal aplasia in patients with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, is a safe and effective treatment that aims to create a functional neovagina. However, rigid vaginal dilators classically described in the literature usually cause physical discomfort and side effects that can lead to vaginal necrosis. Here, we present two cases of MRKH syndrome patients with vaginal agenesis whose main complaint was the inability to have sexual intercourse with their partners. Considering unavailability of acrylic dilators and previous studies reporting good responses with the use of silicone dilators in women with post-radiotherapy vaginal stenosis, the medical team and patients opted for creation of a neovagina through the daily use of silicone vaginal dilators. Patient 1 developed an 8-cm vagina after 6 months of treatment and had a satisfactory sex life with her partner. Patient 2 developed a 7-cm vagina and reported significant symptom improvement. None of the patients developed side effects after the treatment. The use of inexpensive and easily accessible silicone vaginal dilators may be an effective and noninvasive alternative with few side effects for women with vaginal agenesis, particularly in the developing countries.

A 46,XX testicular disorder of sex development caused by a Wilms' tumour Factor-1 (WT1) pathogenic variant.

Molecular diagnosis is rarely established in 46,XX testicular (T) disorder of sex development (DSD) individuals with atypical genitalia. The Wilms' tumour factor-1 (WT1) gene is involved in early gonadal development in both sexes. Classically, WT1 deleterious variants are associated with 46,XY disorders of sex development (DSD) because of gonadal dysgenesis. We report a novel frameshift WT1 variant identified in an SRY-negative 46,XX testicular DSD girl born with atypical genitalia. Target massively parallel sequencing involving DSD-related genes identified a novel heterozygous WT1 c.1453_1456del; p.Arg485Glyfs*14 variant located in the fourth zinc finger of the protein which is absent in the population databases. Segregation analysis and microsatellite analysis confirmed the de novo status of the variant that is predicted to be deleterious by in silico tools and to increase WT1 target activation in crystallographic model. This novel and predicted activating frameshift WT1 variant leading to the 46,XX testicular DSD phenotype includes the fourth zinc-finger DNA-binding domain defects in the genetic aetiology of 46,XX DSD.

Oestrogen receptor alpha expression in neovaginal tissue of women following modified Abbé-McIndoe technique and in premenopausal women.

The aim of the study was to compare the expression of oestrogen receptor alpha (ERα) in neovaginal tissue of patients with vaginal agenesis following neovaginoplasty using regenerated, oxidised cellulose in premenopausal women. A prospective, observational case-control study was performed on eight patients with vaginal agenesis following modified Abbé-McIndoe neovaginoplasty and 10 control premenopausal women following benign gynaecologic surgery. 6F11 monoclonal antibody was used to determine ERα expression in the vaginal mucosa. Quantitative and qualitative evaluations were performed, respectively, in vaginal epithelium and stroma. The thickness of the vaginal epithelium was determined as the vertical distance between the basal layer cells and the apical surface of the superficial layer. The percentage of ERα-expressing cells was higher in the control group, except in the superficial zone of the epithelium. In the stromal tissue, ERα was detected in only one patient from the neovagina group compared with nine women in the control group. The neovagina group had a statistically thinner epithelium. Our study suggests that women with vaginal agenesis following modified Abbé-McIndoe neovaginoplasty using regenerated oxidised, cellulose experience relatively local hypo-oestrogenism in the first year after surgery, with repercussion in vaginal trophism.

Three new SF-1 (NR5A1) gene mutations in two unrelated families with multiple affected members: within-family variability in 46,XY subjects and low ovarian reserve in fertile 46,XX subjects.

BACKGROUND: Three novel heterozygous SF-1 gene mutations affecting multiple members of two unrelated families with a history of 46,XY disorders of sex development (DSD) and 46,XX ovarian insufficiency are described. METHODS: clinical and mutational analysis of the SF-1 gene in 9 subjects of two families. RESULTS: family 1 had 2 affected 46,XY DSD subjects. One, born with severe perineal hypospadias, was raised as a male, and presented normal adolescence. The other, born with ambiguous genitalia, uterus, and mild testicular dysgenesis, was raised as a female. A W279X heterozygous mutation and an intronic deletion (g3314-3317delTCTC (IVS 4 + 8) was found in the SF-1 gene. In family 2, 4/6 affected siblings had 46,XY DSD or hypospadias. An affected 46,XX sister had normal sexual development but increased FSH levels. The 37-year-old affected mother had entered menopause. An Y183X heterozygous mutation was detected. CONCLUSION: an extreme within-family phenotypic variability, ranging from severe prenatal undervirilization to normal pubertal development, was observed in 46,XY-affected siblings, indicating that other unknown factors might be involved in the phenotype. Low ovarian reserve and preserved fertility in 46,XX subjects can be observed in heterozygous SF-1 gene mutations.