Molecular mechanisms of external genitalia development

Maternal PM2.5 exposure and hypospadias risk in Chinese offspring: Insights from a nationwide surveillance-based study

Research on the association between maternal PM2.5 exposure and hypospadias risk in male offspring, particularly in highly polluted areas, has been limited and inconsistent. This study leveraged data from China's National Population-based Birth Defects Surveillance System spanning the years 2013 to 2019, and employed sophisticated machine learning models to estimate daily PM2.5 levels and other pollutants for mothers at a 1-km resolution and a 6-km buffer surrounding maternal residences. Multivariate logistic regression analyses were performed to evaluate the relationship between PM2.5 exposure and hypospadias risk. For sensitivity analyses, stratification analysis was conducted, and models for one-pollutant and two-pollutants, as well as distributed lag nonlinear models, were constructed. Of the 1194,431 boys studied, 1153 cases of hypospadias were identified. A 10 μg/m3 increase in maternal PM2.5 exposure during preconception and the first trimester was associated with an elevated risk of isolated hypospadias, with Odds Ratios (ORs) of 1.102 (95% CI: 1.023-1.188) and 1.089 (95% CI: 1.007-1.177) at the 1-km grid, and 1.122 (95% CI: 1.034-1.218) and 1.143 (95% CI: 1.048-1.246) within the 6-km buffer. Higher quartiles of PM2.5 exposure were associated with increased odds ratios compared to the lowest quartile. These findings highlight a significant association between PM2.5 exposure during the critical conception period and an elevated risk of isolated hypospadias in children, emphasizing the need for targeted interventions to reduce PM2.5 exposure among expectant mothers.

Microphallus early management in infancy saves adulthood sensual life: A ‎‎comprehensive review

Microphallus/Micropenis is a rare condition with significant physical and psychological implications for affected individuals. This article comprehensively reviews micropenis, its etiology, epidemiology, and various treatment options. We conducted a thorough literature review to collect relevant information on micropenis and microphallus, as well as related disorders. Our primary databases were PubMed, Medline, and Google Scholar. We searched for articles published in English between 2000 and 2023. Our analysis included 67 review articles, 56 research studies, 11 case reports, one guideline, and one editorial. Our search terms included "microphallus", "micropenis", "congenital hypogonadotropic hypogonadism", "androgen insensitivity syndrome", "pediatric management of micropenis", "testosterone therapy", and "psychosocial implications of micropenis". We focused on diagnosing micropenis and related conditions, including hormonal assessments, medical and surgical treatment options, psychosocial and psychological well-being, sexual development of adolescents, and sociocultural influences on men's perceptions of penile size. Additionally, we explored parenting and family dynamics in cases of micropenis and disorders of sex development, implications of hormonal treatment in neonates, and studies related to penile augmentation procedures and their effectiveness. The article highlights the importance of early diagnosis and intervention in addressing the physical and psychological well-being of individuals with micropenis. Surgical procedures, such as penile lengthening and girth enhancement, and non-surgical approaches like hormonal therapy are explored. The significance of psychological support, education, and lifestyle modifications is emphasized. Early management and comprehensive care are crucial for individuals with micropenis, from infancy to adolescence and beyond. A multidisciplinary approach involving urologists, endocrinologists, and mental health professionals is recommended. Regular assessment of treatment effectiveness and the need for updated guidelines are essential to provide the best possible care. Healthcare professionals should prioritize early diagnosis, and neonatologists should measure stretched penile length in neonates. A collaborative effort is needed among professionals, parents, and affected individuals to create a supportive environment that recognizes worth beyond physical differences. Continuous research and evidence-based updates are crucial for improving care standards.

46,XX Differences of Sex Development outside congenital adrenal hyperplasia: pathogenesis, clinical aspects, puberty, sex hormone replacement therapy and fertility outcomes

The term 'differences of sex development' (DSD) refers to a group of congenital conditions that are associated with atypical development of chromosomal, gonadal, and/or anatomical sex. DSD in individuals with a 46,XX karyotype can occur due to fetal or postnatal exposure to elevated amount of androgens or maldevelopment of internal genitalia. Clinical phenotype could be quite variable and for this reason these conditions could be diagnosed at birth, in newborns with atypical genitalia, but also even later in life, due to progressive virilization during adolescence, or pubertal delay. Understand the physiological development and the molecular bases of gonadal and adrenal structures is crucial to determine the diagnosis and best management and treatment for these patients. The most common cause of DSD in 46,XX newborns is congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, determining primary adrenal insufficiency and androgen excess. In this review we will focus on the other rare causes of 46,XX DSD, outside CAH, summarizing the most relevant data on genetic, clinical aspects, puberty and fertility outcomes of these rare diseases.

MEHP activates JNK to inhibit the migration of human foreskin fibroblasts

This study aimed to investigate the impact of mono(2-ethylhexyl) phthalate (MEHP) on the proliferation, apoptosis, and migration of human foreskin fibroblast cells (HFF-1) and the role of the JNK signaling pathway in cell migration. HFF-1 cells were randomly assigned to the control group with 0 MEHP exposure (M0) or the experimental groups with 25, 50, 100, 200, and 400 μmol/L MEHP exposure (M25, M50, M100, M200, and M400, respectively). After 24 and 48 h of MEHP exposure, the proliferation of HFF-1 cells in any group had no significant change. However, compared with the M0 group, the M200 and M400 groups presented substantially increased apoptosis of HFF-1 cells. Moreover, cell migration ability significantly decreased in all groups (p < 0.05). Additionally, the transcription and phosphorylated protein activation of JNK kinase in HFF-1 cells were substantially upregulated with the increase in MEHP exposure. Subsequently, HFF-1 cells were randomly divided into three groups: the DMSO blank control group, the 100 μM MEHP experimental group (M100), and the 100 μM MEHP plus 10 μM SP600125 (specific JNK inhibitor) experimental group (S10). The activation of JNK protein in HFF-1 cells was substantially downregulated in the S10 group. HFF-1 cells were also divided into the blank control group (M0). They were treated with 100 μM MEHP and varying concentrations of SP600125 (5, 10, and 15 μM for S5, S10, and S15, respectively). As the concentration of the antagonist increased, the migration ability of HFF-1 cells was returned to normal. Finally, the ROS in HFF-1 cells increased under MEHP exposure. This finding indicates that the regulation of cell migration by the JNK signaling pathway may be important in the occurrence of hypospadias.

A Rare Case of Penoscrotal Webbing and Extensive Hernias: An Anatomical Report With Genetic Insights

During a routine anatomical dissection of an 81-year-old male cadaver received through the Gift Body Program of Saint Louis University School of Medicine (SLU SOM), a massive bulging in the abdominal area was observed that was consistent with numerous hernia repairs noted in the donor's self-reported medical history. Gross anatomical dissection of the cadaveric body revealed extensive herniation of portions of the small intestine and peritoneal sac along the costal margin and extending to the left aspect of the abdomen. Additionally, an uncircumcised phallus was buried within the suprapubic fat pad and demonstrated simple, grade III penoscrotal webbing (PSW), creating an impression of micropenis presence. To gain additional insights into the current case, analysis of the coding regions (exomes) of DNA procured from the body for putative genetic variants was performed using next-generation sequencing (NGS) technology. This analysis revealed 110 rare (minor allele frequency (MAF) ≤ 0.01), pathologic/deleterious genetic mutations. The most relevant variants to this case were the ones associated with male sexual development, BMP1 and BMP4; connective tissue development, COL3A1 and COL5A3; cilia morphogenesis and function, DNAH5 and MAPK15; as well as hormonal homeostasis, ESR1. Direct involvement of BMP1 both in male sexual development and hernia genesis makes it a strong candidate for linking the two pathologies, PSW and multiple hernias, observed in the present case. Yet the presence of a group of mutated genes linked to myopathies (ITGA7, NRAP, POLM, SCN5A, XIRP2) and muscular dystrophy (ITGA7) raises a question about the involvement of these muscular pathologies in hernia genesis and unsuccessful hernia repairs associated with the current case.

hsa_circ_0000417 downregulation suppresses androgen receptor expression and apoptotic signals in human foreskin fibroblasts via sponging miR-6756-5p

BACKGROUND

Dysregulated apoptosis of penile mesenchymal cells during male urethragenesis has been previously demonstrated to underly hypospadiac urethral closure failure, and androgen receptor (AR) has been shown to play a central role in regulating penile mesenchyme cell proliferation and survival. However, the regulatory mechanisms upstream and downstream of AR remain poorly understood. Our clinical data and bioinformatics analysis previously indicated that hsa_circ_0000417, a circRNA significantly downregulated in hypospadias preputial specimens, may act as a ceRNA for AR via sequestering hsa_miR-6756-5p, and that the biological functions of hsa_circ_0000417 may significantly involve the PI3K/AKT pathway. In this study, we employed human foreskin fibroblasts (HFF-1) to experimentally validate this putative hsa_circ_0000417/miR-6756-5p/AR axis and its impact on penile mesenchymal cell proliferation and apoptosis.

METHOD AND RESULTS

We showed that hsa_circ_0000417 knockdown significantly promoted proliferation and suppressed apoptosis of HFF-1 cells. Mechanistically, hsa_circ_0000417 functioned as a molecular sponge for miR-6756-5p in HFF-1 cells and relieved the latter's translational repression on AR mRNA, leading to decreased AKT activation and increased expression of pro-apoptotic proteins BAX and cleaved-caspase 9. Conversely, elevated levels of miR-6756-5p resulted in diminished AR expression concomitant with enhanced AKT activation and HFF-1 cell proliferation.

CONCLUSIONS

Collectively, our data describe for the first time a circRNA-mediated post-transcriptional regulatory mechanism of AR and its functional consequences in penile mesenchymal cells in the context of hypospadias. These findings may contribute to advancing our current understanding of the roles of AR and mesenchymal cell fate decisions during penile morphogenesis.

Development of a Wound-Healing Protocol for In Vitro Evaluation of Urothelial Cell Growth

Urethral healing is plagued by strictures, impacting quality of life and medical costs. Various growth factors (GFs) have shown promise as therapeutic approaches to improve healing, but there is no protocol for in vitro comparison between GFs. This study focuses the development of a biomimetic in vitro urothelial healing assay designed to mimic early in vivo healing, followed by an evaluation of urothelial cell growth in response to GFs.

METHODS

Wound-healing assays were developed with human urothelial cells and used to compared six GFs (EGF, FGF-2, IGF-1, PDGF, TGF-β1, and VEGF) at three concentrations (1 ng/mL, 10 ng/mL, and 100 ng/mL) over a 48 h period. A commercial GF-containing medium (EGF, TGF-α, KGF, and Extract P) and a GF-free medium were used as controls.

RESULTS

There was a statistically significant increase in cell growth for IGF-1 at 10 and 100 ng/mL compared to both controls (p < 0.05). There was a statistically significant increase in cell growth for EGF at all concentrations compared to the GF-free medium control (p < 0.05).

CONCLUSION

This study shows the development of a clinically relevant wound-healing assay to evaluate urothelial cell growth. It is the first to compare GFs for future use in reconstructive techniques to improve urethral healing.

A Genetics Study in the Foreskin of Boys with Hypospadias

Introduction

Hypospadias is a malformation of the genitourinary system in males, characterized by the placement of the urethral opening in the ventral surface of the penis. Although controversies continue about etiology, endocrine disrupting chemicals that disrupt normal endocrine signaling at the receptor or signal transduction level are thought to play an essential role in etiology. This study aimed to investigate the receptor gene expressions of the sex hormones and FGFR2, HOXA13, and TGFB1, which are considered to play an essential role in developing hypospadias.

Methods

The samples from the foreskin of 26 patients with hypospadias and 26 healthy children who underwent circumcision operations were collected. ESR1, AR, FGFR2, HOXA13, and TGFB gene expressions were investigated by real-time PCR in samples obtained during surgery.

Results

In the hypospadias group, ESR1 expression was increased (p = 0.013), and AR and FGFR2 expressions were decreased, which were found to be statistically significant (p = 0.027 and p = 0.003, respectively). There was no statistically significant difference between hypospadias and control groups in TGFBand HOXA13expression levels (p > 0.05).

Discussion

The results suggest that sex hormone receptors and FGFR2 may play an essential role in developing male external genital structures at the gene level. The defects in the expression of these genes can contribute to understanding the development of hypospadias.

Role of epigenetics in the etiology of hypospadias through penile foreskin DNA methylation alterations

Abnormal penile foreskin development in hypospadias is the most frequent genital malformation in male children, which has increased dramatically in recent decades. A number of environmental factors have been shown to be associated with hypospadias development. The current study investigated the role of epigenetics in the etiology of hypospadias and compared mild (distal), moderate (mid shaft), and severe (proximal) hypospadias. Penile foreskin samples were collected from hypospadias and non-hypospadias individuals to identify alterations in DNA methylation associated with hypospadias. Dramatic numbers of differential DNA methylation regions (DMRs) were observed in the mild hypospadias, with reduced numbers in moderate and low numbers in severe hypospadias. Atresia (cell loss) of the principal foreskin fibroblast is suspected to be a component of the disease etiology. A genome-wide (> 95%) epigenetic analysis was used and the genomic features of the DMRs identified. The DMR associated genes identified a number of novel hypospadias associated genes and pathways, as well as genes and networks known to be involved in hypospadias etiology. Observations demonstrate altered DNA methylation sites in penile foreskin is a component of hypospadias etiology. In addition, a potential role of environmental epigenetics and epigenetic inheritance in hypospadias disease etiology is suggested.

Morphology of the urogenital papilla of the male marine teleost Black Rockfish, Sebastes schlegelii (Hilgendorf, 1880), and its role in internal fertilization

There are few detailed descriptions of the morphology of the male external genitalia, the urogenital papilla (UGP), of the Black Rockfish (Sebastes schlegelii Hilgendorf, 1880). The purpose of this study was to evaluate this organ histologically and to determine the time of development of the UGP in Black Rockfish. Twelve adult males, three adult females and around 500 juveniles were used in the experiment. The juveniles were divided into normal developmental and androgen groups. The androgen group was exposed to methyltestosterone (100 μg/L) for 2 h daily for 38 days. Samples (N = 10 per sampling) were randomly selected for analysis every 5 days from 30 to 116 days after birth. Parameters assessed included the type of epithelium, composition of connective tissue, muscular tissue, and the timing of UGP development. Differences in these parameters between normal developmental and androgen groups were evaluated. The results indicated that the UGP of the adult fish contains the sperm duct and ureter, which have the function of transporting sperm and urine, respectively. The androgen-treated juvenile fish developed the UGP earlier than the normal development group. This study provides a reference for understanding the external genitalia of other viviparous fishes by studying the UGP of the male Black Rockfish.

Pregnancy outcomes following maternal macrolide use: A systematic review and meta-analysis

To determine whether gestational use of all or specific macrolides (azithromycin, clarithromycin, roxithromycin or erythromycin) lead to an increase in rates of overall major congenital malformations, organ-specific malformations, and other adverse pregnancy outcomes in infants. PubMed/MEDLINE, Cochrane Central Register of Controlled Trials and Reprotox® databases were searched. Dichotomous outcomes or calculated log odds ratios and standard errors from observational studies are combined using the random-effects method in Review Manager 5.3. No significant increased risks for major congenital malformation (OR 1.06 [95% CI 0.99, 1.13]) and congenital heart defect (OR 1.05 [95% CI 0.92, 1.19]) following all macrolides use during the first trimester were detected. Prenatal azithromycin use was associated with a significantly increased risk of major congenital malformations in the analysis of cohort studies (OR 1.21 [95% CI 1.08-1.36]). This significance was also present in the sensitivity analysis. There were no statistically significant associations between the risk of organ specific malformations and all or specific macrolide exposures except for the decreased risk in hypospadias following erythromycin use in the meta-analysis of case-control studies (OR 0.38 [95% CI 0.18, 0.81]. Also, a significant 1.5-fold increased risk for spontaneous abortion following macrolide use was detected. A slight yet significantly increased rate of major congenital malformation with azithromycin exposure during pregnancy may be associated with maternal confounders. Nevertheless, level II ultrasound can be suggested following maternal azithromycin use during the first trimester. Future studies should take into account the inclusion of a disease-matched control group and accurate classification of the malformations.

Use of an Autologous Platelet-Rich Concentrate in Hypospadias Repair: A Systematic Review and Meta analysis

Background

There is unanimous agreement amongst hypospadias surgeons to use an intermediate layer to cover the neourethra. Dartos fascia and tunica vaginalis (TV) flaps are the most preferred tissues to be used. Tissue glue, sealants and biomaterials are also useful where there is a paucity of local tissue to cover the neourethra. But these blood-derived products have associated infectious and allergic risks. The autologous human platelet concentrate (APC) contains biologically active factors and is safe for wound healing and soft tissue reconstruction. It has been used by few surgeons as an intermediate layer in hypospadias repair. This systematic review and meta-analysis aim to systematically compare the outcomes of hypospadias surgery in children with or without using APCs.

Methods

This systematic review and meta-analysis was conducted as per the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Meta-analysis protocol was registered with INPLASY. A systematic, detailed search was carried out by the authors in the electronic databases, including Medline, Embase, CENTRAL, Scopus, Google Scholar and clinical trial registry. Studies were selected and compared based on primary outcome measures like urethra-cutaneous fistula, meatal stenosis, wound infection and operative time. Statistical analysis was performed using a fixed-effect model, pooled risk ratio and I2 heterogeneity.

Results

Four randomized studies with a total of 355 patients were included. Pooled analysis for outcome of urethra-cutaneous fistula (UCF) showed no significant difference between the groups with APC and without APC. Pooled analysis for the other outcome like meatal stenosis, wound infection and total complications showed a decrease in incidence of these complications in groups with APC.

Conclusion

This meta-analysis shows that there is a reduction in the incidence of wound infection, meatal stenosis and total complications in patients where APC was used to cover the neourethra, although no such difference was observed in UCF rates.

Hypospadias: A Comprehensive Review Including Its Embryology, Etiology and Surgical Techniques

Hypospadias is among the most prevalent urogenital malformations in male newborns. It is characterized by the displacement of the urethral meatus to the ventral side of the penis, an aberrant ventral curve of the penis referred to as "chordee," and an abnormally arranged foreskin with a "hood" found dorsally and lacking foreskin ventrally. Patients may have an extra genitourinary abnormality based on the area of the lesion. In around 70% of cases, the urethral meatus is positioned distally to the shaft, representing a milder form of the disease. The remaining 30% of cases are located proximally, are more complicated, and require further evaluation. Although the origin of hypospadias is mostly obscure, several suggestions exist about genetic susceptibility and hormonal factors. The objective of hypospadias restoration is to restore aesthetic and functional regularity, and surgery is currently advised at a young age, mostly between six and 18 months. At any age, hypospadias can be repaired with an equivalent risk of complications, functional outcomes, and aesthetic outcomes. However, the best age of treatment is still undetermined. Even though the long-term effects on appearance and sexual function are usually good, males may be less likely to make the first move after rectification. Also, people who have hypospadias treated are twice as likely to have problems with their lower urinary tract. These problems can last for years after the initial repair.

Characterization of Associated Nonclassical Phenotypes in Patients with Deletion in the WAGR Region Identified by Chromosomal Microarray: New Insights and Literature Review

WAGR syndrome (Wilms' tumor, aniridia, genitourinary changes, and intellectual disability) is a contiguous gene deletion syndrome characterized by the joint deletion of PAX6 and WT1 genes, located in the short arm of chromosome 11. However, most deletions include other genes, leading to multiple associated phenotypes. Therefore, understanding how genes deleted together can contribute to other clinical phenotypes is still considered a challenge. In order to establish genotype-phenotype correlation in patients with interstitial deletions of the short arm of chromosome 11, we selected 17 patients with deletions identified by chromosomal microarray analysis: 4 new subjects and 13 subjects previously described in the literature with detailed clinical data. Through the analysis of deleted regions and the phenotypic changes, it was possible to suggest the contribution of specific genes to several nonclassical phenotypes, contributing to the accuracy of clinical characterization of the syndrome and emphasizing the broad phenotypic spectrum found in the patients. This study reports the first patient with a PAX6 partial deletion who does not present any eye anomaly thus opening a new set of questions about the functional activity of PAX6.

The Fate of Leydig Cells in Men with Spermatogenic Failure

The steroidogenic cells in the testicle, Leydig cells, located in the interstitial compartment, play a vital role in male reproductive tract development, maintenance of proper spermatogenesis, and overall male reproductive function. Therefore, their dysfunction can lead to all sorts of testicular pathologies. Spermatogenesis failure, manifested as azoospermia, is often associated with defective Leydig cell activity. Spermatogenic failure is the most severe form of male infertility, caused by disorders of the testicular parenchyma or testicular hormone imbalance. This review covers current progress in knowledge on Leydig cells origin, structure, and function, and focuses on recent advances in understanding how Leydig cells contribute to the impairment of spermatogenesis.

Abnormal placental cord insertion, hypertensive disorders of pregnancy and birth length may be involved in development of hypospadias in male fetuses

Objectives

Hypospadias is a congenital disease characterized by morphological abnormalities of the penis, including abnormal urethral opening and penile flexion, which cause urination disorders and/or sexual intercourse difficulty. Various factors have been suggested to cause this anomaly, but evidence concerning risk factors causing this anomaly is insufficient. We evaluated the etiology of hypospadias in Japan using the Common Database of the National Hospitals' Neonatal study group.

Study design

We retrospectively evaluated 7,865 male neonates registered in the NICU Common Database of the National Hospitals' Neonatal study group. The subjects were divided into two groups by the presence (n = 43) or absence (n = 7,822) of hypospadias. Statistical analyses were performed to compare nominal variables between the groups by Fisher's direct establishment calculation method and logistic regression analyses.

Results

A univariate analysis showed significant between‐group differences in hypertensive disorders in pregnancy (odds ratio [OR]: 4.02, 95% confidence interval [CI]: 1.95–7.90), placental weight <−1.28 standard deviation (SD; OR: 5.06, 95% CI: 2.45–10.32), abnormal placental cord insertion (OR: 4.7, 95% CI: 2.62–9.76), birth length <−2SD (OR: 10.56, 95% CI: 5.00–21.1) and birth weight <−2SD (OR: 8.17, 95% CI: 4.17–15.68). A multivariate analysis showed a significant between‐group difference in hypertensive disorders of pregnancy (adjusted OR [AOR]: 2.30, 95% CI: 1.09–4.85), abnormal placental cord insertion (AOR: 3.69, 95% CI: 1.83–7.44) and birth length <−2SD (AOR: 3.44, 95% CI: 1.26–9.42).

Conclusion

Abnormal placental cord insertion, hypertensive disorders of pregnancy and birth length may be involved in hypospadias development in male neonates in conjunction with placental dysfunction in early pregnancy.

Urethral mobilization and advancement technique in distal types of hypospadias: short-term local experience

Background

A prospective study was conducted on 65 cases with distal hypospadias operated using the urethral mobilization technique between July 2017 and December 2019. Patients with proximal hypospadias and those with distal hypospadias, but with a hypoplastic urethra, were excluded from the study. In this technique, the urethral tube was mobilized proximally in a ratio of 3–4:1 (the ratio of mobilized urethral length to the initial distance between the native meatus and the tip of the glans) then positioned distally after creating wide glans wings. The aim of this study was to assess the outcome of the urethral mobilization technique in distal hypospadias in our center.

Results

The age of patients was ranged 9 months to 7 years old (mean 37.5 months); 17 (26%) cases were already circumcised. During the postoperative follow-up, 62 (95.4%) patients had a good caliber neomeatus with a good and straight urinary stream; the remaining 3 (4.6%) cases developed meatal stenosis which responded well to urethral dilatation. One (1.5%) patient had a minor retraction of neomeatus but remained within the glans and not requiring further intervention. Four (6%) cases developed minor hematoma which was resolved on conservative measures. Six (9.2%) patients developed minor wound infection which was treated with daily dressing and antibiotic coverage.

Conclusion

The urethral mobilization technique is a good choice for repairing distal hypospadias especially for boys who are previously circumcised as the preputial flap is not required in this technique. It provides good cosmetic and functional results, with a fewer complication rate.

Female congenital aphallia: a unique case of congenital absence of the clitoris with an ectopic labium majorum

The spectrum of disorders of sexual development includes anatomical abnormalities of the external genitalia, the phenotypic variability of which and the underlying causes are numerous. However, female aphallia and ectopia of the labium majorum appear to be some of the rarest forms of external genitalia malformations. Aphallia is mostly described in males with a frequency of less than one per 40 000 male newborns. Although syndromic forms of aphallia in females have been reported, for example, in Robinow, CHARGE, and Prader-Willi syndrome, reports of isolated female aphallia are meager. Here, we describe the first case of isolated agenesis of the clitoris with an ectopic labium majorum and review the literature of this uncommon malformation and its potential dysmorphogenetic mechanism. We emphasize the need for a routine exhaustive physical examination to identify and characterize this unusual malformation correctly so that families can be appropriately counseled as to cause and potential complications.

46,XX DSD: Developmental, Clinical and Genetic Aspects

Differences in sex development (DSD) in patients with 46,XX karyotype occur by foetal or postnatal exposure to an increased amount of androgens. These disorders are usually diagnosed at birth, in newborns with abnormal genitalia, or later, due to postnatal virilization, usually at puberty. Proper diagnosis and therapy are mostly based on the knowledge of normal development and molecular etiopathogenesis of the gonadal and adrenal structures. This review aims to describe the most relevant data that are correlated with the normal and abnormal development of adrenal and gonadal structures in direct correlation with their utility in clinical practice, mainly in patients with 46,XX karyotype. We described the prenatal development of structures together with the main molecules and pathways that are involved in sex development. The second part of the review described the physical, imaging, hormonal and genetic evaluation in a patient with a disorder of sex development, insisting more on patients with 46,XX karyotype. Further, 95% of the etiology in 46,XX patients with disorders of sex development is due to congenital adrenal hyperplasia, by enzyme deficiencies that are involved in the hormonal synthesis pathway. The other cases are explained by genetic abnormalities that are involved in the development of the genital system. The phenotypic variability is very important in 46,XX disorders of sex development and the knowledge of each sign, even the most discreet, which could reveal such disorders, mainly in the neonatal period, could influence the evolution, prognosis and life quality long term.

Genitourinary Tissue Engineering: Reconstruction and Research Models

Tissue engineering is an emerging field of research that initially aimed to produce 3D tissues to bypass the lack of adequate tissues for the repair or replacement of deficient organs. The basis of tissue engineering protocols is to create scaffolds, which can have a synthetic or natural origin, seeded or not with cells. At the same time, more and more studies have indicated the low clinic translation rate of research realised using standard cell culture conditions, i.e., cells on plastic surfaces or using animal models that are too different from humans. New models are needed to mimic the 3D organisation of tissue and the cells themselves and the interaction between cells and the extracellular matrix. In this regard, urology and gynaecology fields are of particular interest. The urethra and vagina can be sites suffering from many pathologies without currently adequate treatment options. Due to the specific organisation of the human urethral/bladder and vaginal epithelium, current research models remain poorly representative. In this review, the anatomy, the current pathologies, and the treatments will be described before focusing on producing tissues and research models using tissue engineering. An emphasis is made on the self-assembly approach, which allows tissue production without the need for biomaterials.

Androgenization in Klinefelter syndrome: Clinical spectrum from infancy through young adulthood

Klinefelter syndrome (KS) is an uncommon chromosomal disorder in males that has a variable clinical appearance. Classic KS involves an extra X chromosome, (47, XXY), although other variations may exist, including a milder mosaic form as well as multiple extra sex chromosomes with more dramatic phenotypes. KS is underdiagnosed, especially pre-pubertally, owing to a paucity of concrete clinical signs; however, diagnostic rates increase during and after puberty, as the consequences of hypergonadotropic hypogonadism begin to manifest. Testicular failure causing decreased circulating testosterone (T) and germ cell depletion, a hallmark feature in KS, commonly begins shortly after the onset of puberty and leads to the most commonly recognized KS traits: small testes, azoospermia, gynecomastia, decreased facial and pubic hair. While many KS men maintain adequate T levels leading up to young adulthood, some may have lower T levels at an earlier age leading to varied levels of androgenization and clinical KS features. At certain critical time points, absent or decreased T may alter the development of normal male reproductive organs, external genitalia, development of secondary sexual characteristics and spermatogenesis. Testicular failure in utero may lead to ambiguous genitalia, cryptorchidism and/or hypospadias, all of which depend on fetal T production. In the neonatal period and childhood, decreased T levels during the mini-puberty of infancy may negatively impact germ cell differentiation and male neuropsychological development. Finally, decreased T during pubertal and young adulthood can lead to decreased virilization during puberty, eunuchoid skeleton and decreased spermatogenesis. Depending on the timing of the testicular failure, a reproductive window of sperm production may exist to achieve paternity for KS men. The presence or absence of clinical characteristics reflecting decreased androgenization provides an insight to the relative testicular function during these developmental time points for those with KS and contributes to variability within the syndrome.

Molecular mechanisms of estrogen action in female genital tract development

The development of the female reproductive tract can be divided into three parts consisting of Müllerian duct organogenesis, pre-sexual maturation organ development, and post-sexual maturation hormonal regulation. In primates, Müllerian duct organogenesis proceeds in an estrogen independent fashion based on transcriptional pathways that are suppressed in males by the presence of AMH and SRY. However, clinical experience indicates that exposure to xenoestrogens such as diethylstilbestrol (DES) during critical periods including late organogenesis and pre-sexual maturational development can have substantial effects on uterine morphology, and confer increased risk of disease states later in life. Recent evidence has demonstrated that these effects are in part due to epigenetic regulation of gene expression, both in the form of aberrant CpG methylation, and accompanying histone modifications. While xenoestrogens and selective estrogen receptor modulators (SERMS) both can induce non-canonical binding confirmations in estrogen receptors, the primate specific fetal estrogens Estriol and Estetrol may act in a similar fashion to alter gene expression through tissue specific epigenetic modulation.

Expression of Mafb is down-regulated in the foreskin of children with hypospadias

BACKGROUND

Hypospadias is the second most common congenital malformation in males. Although the aetiology of hypospadias is not clear, it is generally thought to be affected by both genetic and environmental endocrine-disrupting factors that affect the development of the urethra, leading to deformity.

OBJECTIVE

To investigate the difference in expression of the transcription factor Mafb in hypospadias and normal penile tissues and to assess whether it is related to the occurrence of hypospadias.

STUDY DESIGN

Penile tissue was obtained from children with hypospadias who underwent surgical repair at the Children's Hospital of Chongqing Medical University. Patients diagnosed with undescended testicles, intersex status or endocrine abnormalities were excluded from the study. Twenty-five cases with hypospadias (average 3.5 years old) and 15 cases with circumcisions (as control) (average 5 years old) were included in this study. Real-time quantitative polymerase chain reaction, Immunochemistry and Western blot were used to detect the expression of Mafb.

RESULTS

Mafb mRNA expressions in the prepuce of cases with hypospadias was significantly reduced compared with that in the controls [(1.179 ± 0.1275), (0.6652 ± 0.07506), p < 0.05)]. Hypospadias cases also showed decreased Mafb protein expression in the preputial subcutaneous mesenchymal cell layer. Mafb protein levels were significantly decreased in those with hypospadias compared with controls [(1.932 ± 0.1139), (1.006 ± 0.03312), p < 0.05]. However, no such differences were found in Mafb expression between subjects with mild and severe hypospadias.

DISCUSSION

Compared to the normal foreskin, expression of the Mafb gene was down-regulated at both mRNA and protein levels, which was consistent with our RNA-seq sequencing results in Diethylhexyl phthalate (DEHP)-induced hypospadias rats. This study is the first to report abnormal expression of Mafb in the preputial tissue of hypospadias cases. An in-depth study of the relationship between Mafb and cell proliferation, apoptosis, and urethra development may reveal the pathogenesis of hypospadias.

CONCLUSION

Expression of the Mafb gene and protein in the foreskin of children with hypospadias is lower than that in normal foreskin. We postulate that such abnormal expression of the Mafb gene may be related to the occurrence of hypospadias and that this abnormal expression may affect the development of the urethra during the embryonic period.

The effects of NONRATT008453.2 on autophagy in genital tubercle fibroblasts of rats with hypospadias induced by dibutyl phthalate

BACKGROUND

Hypospadias is a common birth defect that might be caused by inadequate fusion of the urethral folds in the process of male external genital development. We intended to discover the crucial long noncoding RNAs (lncRNAs) regulating autophagy from the gene expression profile of the genital tubercle (GT) of dibutyl phthalate (DBP) induced hypospadiac rats.

METHODS

Whole transcriptome resequencing was used to determine the expression of the total RNA in GTs and cultured fibroblasts obtained from GTs of DBP-induced hypospadiac male rat fetuses. Autophagosomes and autolysosomes were examined under a transmission electron microscope after overexpression of lncRNA NONRATT008453.2 in the fibroblasts by adenovirus transfection. Finally, the protein expression levels of Atg5, Beclin-1, Atg7, and the LC3A/B-II:LC3A/B-I ratio were detected in the fibroblasts by western blotting.

RESULTS

NONRATT008453.2 suppressed autophagy by promoting the expression of Atg7, but inhibited the expressions of Atg5, Beclin-1, and the LC3A/B-II:LC3A/B-I ratio in the GT fibroblasts.

CONCLUSIONS

NONRATT008453.2 may have an influence on autophagy in the fibroblasts of the GT in DBP-induced hypospadiac rats.

Endocrine Disrupting Chemicals and Reproductive Health in Boys and Men

Male reproductive health has declined as indicated by increasing rates of cryptorchidism, i.e., undescended testis, poor semen quality, low serum testosterone level, and testicular cancer. Exposure to endocrine disrupting chemicals (EDCs) has been proposed to have a role in this finding. In utero exposure to antiandrogenic EDCs, particularly at a sensitive period of fetal testicular development, the so-called 'masculinization programming window (MPW)', can disturb testicular development and function. Low androgen effect during the MPW can cause both short- and long-term reproductive disorders. A concurrent exposure to EDCs may also affect testicular function or damage testicular cells. Evidence from animal studies supports the role of endocrine disrupting chemicals in development of male reproductive disorders. However, evidence from epidemiological studies is relatively mixed. In this article, we review the current literature that evaluated relationship between prenatal EDC exposures and anogenital distance, cryptorchidism, and congenital penile abnormality called hypospadias. We review also studies on the association between early life and postnatal EDC exposure and semen quality, hypothalamic-pituitary-gonadal axis hormone levels and testicular cancer.

Etiology of Hypospadias: A Comparative Review of Genetic Factors and Developmental Processes Between Human and Animal Models

Hypospadias is a congenital anomaly of the penis with an occurrence of approximately 1 in 200 boys, but the etiology of the majority of hypospadias has remained unknown. Numerous genes have been reported as having variants in hypospadias patients, and many studies on genetic deletion of key genes in mouse genital development have also been published. Until now, no comparative analysis in the genes related literature has been reported. The basic knowledge of penile development and hypospadias is mainly obtained from animal model studies. Understanding of the differences and similarities between human and animal models is crucial for studies of hypospadias. In this review, mutations and polymorphisms of hypospadias-related genes have been compared between humans and mice, and differential genotype–phenotype relationships of certain genes between humans and mice have been discussed using the data available in PubMed and MGI online databases, and our analysis only revealed mutations in seven out of 43 human hypospadias related genes which have been reported to show similar phenotypes in mutant mice. The differences and similarities in the processes of penile development and hypospadias malformation among human and commonly used animal models suggest that the guinea pig may be a good model to study the mechanism of human penile development and etiology of hypospadias.

Maternal Exposure to Disinfection By-Products and Risk of Hypospadias in the National Birth Defects Prevention Study (2000-2005)

The purpose of this study was to estimate the association between 2nd and 3rd degree hypospadias and maternal exposure to disinfection by-products (DBPs) using data from a large case-control study in the United States. Concentration estimates for total trihalomethanes (TTHMs), the sum of the five most prevalent haloacetic acids (HAA5), and individual species of each were integrated with data on maternal behaviors related to water-use from the National Birth Defects Prevention Study (NBDPS) to create three different exposure metrics: (1) household DBP concentrations; (2) estimates of DBP ingestion; (3) predicted uptake (i.e., internal dose) of trihalomethanes (THMs) via ingestion, showering, and bathing. The distribution of DBP exposure was categorized as follows: (Q1/referent) < 50%; (Q2) ≥ 50% to < 75%; and (Q3) ≥ 75%. Logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs). Generally, null associations were observed with increasing TTHM or HAA5 exposure. An increased risk was observed among women with household bromodichloromethane levels in the second quantile (aOR: 1.8; 95% CI: 1.2, 2.7); however, this association did not persist after the inclusion of individual-level water-use data. Findings from the present study do not support the hypothesis that maternal DBP exposures are related to the occurrence of hypospadias.

The effect of zinc sulfate on penile corpus spongiosum after hypospadias repair in rats: A stereological study

Hypospadias repair involves correcting urethra defects and improving the wound healing process. Zinc has been well accepted as an effective agent in wound healing. This study aimed to investigate the effect of zinc on corpus spongiosum after experimental hypospadias in rats. The animals were divided into three groups. The control group rats underwent general anesthesia, but did not receive any surgeries and treatments. The second and third groups underwent surgeries and respectively received Distilled Water (DW, 2 ml) and zinc sulfate solution (2 ml, containing 4 mg zinc sulfate) by gavages twice a day for 14 days. Stereological methods were used to quantify the corpus spongiosum tissue. The volumes of corpus spongiosum, spongy tissue, urethral lumens, urethral epithelium, and collagen bundles and the number of fibroblasts were respectively amplified by 28%, 40%, 36%, 48%, 40%, and 29% in the surgery + zinc sulfate group in comparison to the surgery + DW group (p < 0.02). It can be concluded that consumption of 4 mg/day zinc sulfate for 14 days could improve the healing of hypospadias through increasing the population of fibroblasts, producing collagen bundles, and building a wider lumen and more epithelized urethra.

An Unusual Case of Testicular Disorder in Sex Development of Arabian Mare (64,XX SRY-Negative)

Simple Summary

An interesting case of a horse with an XX, SRY-negative disorder of sexual development (DSD) is reported in this paper. In particular, the animal showed the development of both male and female portions of reproductive organs. The possible genetic background of this abnormality is also discussed.

Abstract

A 3-year-old Arabian mare underwent medical examinations due to the presence of abnormalities of the reproductive apparatus and stallion behavior (nervous temperament, aggressiveness, masculine attitude). During the clinical visit, an anovulvar distance shorter than normal was observed; moreover, vulvar lips were dorsally fused except for the lower neckline, showing a blind ending from which a penis-like structure protruded. The ultrasound examination revealed the presence of a cervix and corpus of a uterus, hypoplastic uterine horns, and small gonads with an echogenicity similar to a testis. Blood testosterone levels ranged from 0.4 to 0.6 ng/mL. Cytogenetic analysis showed a normal female karyotype (2n = 64,XX), while PCR amplification of SRY and ZFY genes revealed the absence of a Y chromosome. At necroscopic examination, internal genitalia arising from the genital ridge in the form of masculine type structures were found, while those deriving from the Mullerian ducts were of feminine type. In addition, an infundibular portion of the salpinx at the cranial pole of the gonads was found. This is the first case in equine species of DSD 2n = 64,XX SRY-negative, with the simultaneous presence of male (hypoplastic testicles, epididymal portions, and a penis-like structure) and female (cervix, horn and body of a hypoplastic uterus) genital structures.

Discordant fetal sex on NIPT and ultrasound

Prenatal diagnosis of sex discordance is a relatively new phenomenon. Prior to cell-free DNA testing, the diagnosis of a disorder of sexual differentiation was serendipitous, either through identification of ambiguous genitalia at the midtrimester morphology ultrasound or discovery of genotype-phenotype discordance in cases where preimplantation genetic diagnosis or invasive prenatal testing had occurred. The widespread integration of cfDNA testing into modern antenatal screening has made sex chromosome assessment possible from 10 weeks of gestation, and discordant fetal sex is now more commonly diagnosed prenatally, with a prevalence of approximately 1 in 1500-2000 pregnancies. Early detection of phenotype-genotype sex discordance is important as it may indicate an underlying genetic, chromosomal or biochemical condition and it also allows for time-critical postnatal treatment. The aim of this article is to review cfDNA and ultrasound diagnosis of fetal sex, identify possible causes of phenotype-genotype discordance and provide a systematic approach for clinicians when counseling and managing couples in this circumstance.

A case series of infants with increased VAMP7 gene dosage at birth and virilization defects

BACKGROUND

Genitourinary disorders are the most frequent congenital defects in newborns; however, little is known about their etiology. Several studies have been carried out to find genetic risk factors in the development of these malformations. The expression of VAMP7 is found in testes, epididymis, seminal vesicles, prostatic tissues, penis, and urethra. Alterations in gene dose of VAMP7 were recently reported in a subset of male patients initially identified clinically by the presence of congenital genitourinary disorders. In 2016, the authors developed a diagnostic algorithm for early detection of sex chromosome aneuploidies by quantifying the SHOX, VAMP7, and SRY gene dose in newborns by qPCR using dried blood spot (DBS) samples.

OBJECTIVE

Correlate the increased gene dose of VAMP7, obtained by qPCR using DBS, with genitourinary congenital defects attributable to disorders in virilization and verify the increased gene dose by microarrays.

STUDY DESIGN

Samples that only presented increased VAMP7 gene dosage were selected from a previously analyzed group of 5088 males in which the early detection of sex chromosomes aneuploidies was performed. Eight males were found with an increased gene dose of VAMP7 (relative quantitation > 1.3) and were called in for a complete clinical evaluation aimed at the identification of genitourinary anomalies, qPCR and microarrays.

RESULTS

Eight males from 5088 samples were identified with increased VAMP7 gene dosage of which six patients were clinically evaluated, of which 50% were identified with alterations in genital development (bilateral cryptorchidism, unilateral cryptorchidism, and glandular hypospadias) and speech delay, while the rest presented different types of atopy.

DISCUSSION

Tannour-Louet et al. postulated on 2014 that the duplication of the Xq28 region, specifically of VAMP7, plays a role in the human masculinization disorders of the urogenital tract. The study was based on array comparative genomic hybridization (aCGH) results performed to 116 males with disorders of sexual differentiation. In the present study, the patients were initially selected due to an increased gene dose of VAMP7 detected by qPCR, then the clinical evaluation and the aCGH were performed, inverse to what was reported previously but with similar percentages between both studies.

CONCLUSION

In this work, the authors report cases of cryptorchidism, hypospadias, language delay and atopy in male preschoolers initially identified because they have an increased gene dose of VAMP7.

Perioperative complications within 30 days of hypospadias surgery: Results from NSQIP-Pediatrics

INTRODUCTION

There are no large multi-institutional studies reporting on perioperative complications of hypospadias repairs. We sought to determine perioperative complications of hypospadias repairs from the National Surgical Quality Improvement Program Pediatrics (NSQIP-P) to aid in patient counseling.

STUDY DESIGN

This cohort study from 2012 to 2017 was conducted using NSQIP-P database. Pediatric patients undergoing hypospadias surgery were identified and compared based on 4 major categories: distal/midshaft repair, one-stage repair proximal, stage one repair, and stage two repair. Baseline demographics between the four groups and perioperative parameters were compared. Multivariable logistic regression analysis models including type of repair was used to determine associations with overall complications, infectious complications, and dehiscence.

DISCUSSION

There were 11,292 patients identified in the study population. Overall, 78% underwent distal/midshaft hypospadias repair, 12% underwent one-stage proximal repair, 1.4% underwent proximal first stage repair and 9% underwent proximal second stage repair. Multivariable logistic regression analysis revealed that proximal first stage procedures had similar overall complications to distal/mid repairs but proximal one-stage and proximal second stage procedures were associated with significantly more overall complications, local infectious complications, and dehiscence. Age, race, operative time, prematurity were also independently associated with increased overall complications. As expected, complication rates are higher in those with proximal hypospadias. In staged hypospadias, first stage has a lower complication rate compared to second stage. All complications, especially of infectious and dehiscence are the highest in the one-stage proximal and proximal second stage repairs.

CONCLUSION

We report large multi-institutional analysis of 30-day peri-operative hypospadias repair complications; this information is useful for patient counseling and education.

Consequences of steroid-5α-reductase deficiency and inhibition in vertebrates

In 1974, a lack of 5α-dihydrotestosterone (5α-DHT), the most potent androgen across species except for fish, was shown to be the origin of a type of pseudohermaphrodism in which boys have female-like external genitalia. This human intersex condition is linked to a mutation in the steroid-5α-reductase type 2 (SRD5α2) gene, which usually produces an important enzyme capable of reducing the Δ⁴-ene of steroid C-19 and C-21 into a 5α-stereoisomer. Seeing the potential of SRD5α2 as a target for androgen synthesis, pharmaceutical companies developed 5α-reductase inhibitors (5ARIs), such as finasteride (FIN) and dutasteride (DUT) to target SRD5α2 in benign prostatic hyperplasia and androgenic alopecia. In addition to human treatment, the development of 5ARIs also enabled further research of SRD5α functions. Therefore, this review details the morphological, physiological, and molecular effects of the lack of SRD5α activity induced by both SRD5α mutations and inhibitor exposures across species. More specifically, data highlights 1) the role of 5α-DHT in the development of male secondary sexual organs in vertebrates and sex determination in non-mammalian vertebrates, 2) the role of SRD5α1 in the synthesis of the neurosteroid allopregnanolone (ALLO) and 5α-androstane-3α,17β-diol (3α-diol), which are involved in anxiety and sexual behavior, respectively, and 3) the role of SRD5α3 in N-glycosylation. This review also features the lesser known functions of SRD5αs in steroid degradation in the uterus during pregnancy and glucocorticoid clearance in the liver. Additionally, the review describes the regulation of SRD5αs by the receptors of androgens, progesterone, estrogen, and thyroid hormones, as well as their differential DNA methylation. Factors known to be involved in their differential methylation are age, inflammation, and mental stimulation. Overall, this review helps shed light on the various essential functions of SRD5αs across species.

Analysis of variants in GATA4 and FOG2/ZFPM2 demonstrates benign contribution to 46,XY disorders of sex development

Background

GATA‐binding protein 4 (GATA4) and Friend of GATA 2 protein (FOG2, also known as ZFPM2) form a heterodimer complex that has been shown to influence transcription of genes in a number of developmental systems. Recent evidence has also shown these genes play a role in gonadal sexual differentiation in humans. Previously we identified four variants in GATA4 and an unexpectedly large number of variants in ZFPM2 in a cohort of individuals with 46,XY Differences/Disorders of Sex Development (DSD) (Eggers et al, Genome Biology, 2016; 17: 243).

Method

Here, we review variant curation and test the functional activity of GATA4 and ZFPM2 variants. We assess variant transcriptional activity on gonadal specific promoters (Sox9 and AMH) and variant protein–protein interactions.

Results

Our findings support that the majority of GATA4 and ZFPM2 variants we identified are benign in their contribution to 46,XY DSD. Indeed, only one variant, in the conserved N‐terminal zinc finger of GATA4, was considered pathogenic, with functional analysis confirming differences in its ability to regulate Sox9 and AMH and in protein interaction with ZFPM2.

Conclusions

Our study helps define the genetic factors contributing to 46,XY DSD and suggests that the majority of variants we identified in GATA4 and ZFPM2/FOG2 are not causative.

Histology Atlas of the Developing Mouse Urinary System With Emphasis on Prenatal Days E10.5-E18.5

Congenital abnormalities of the urinary tract are some of the most common human developmental abnormalities. Several genetically engineered mouse models have been developed to mimic these abnormalities and aim to better understand the molecular mechanisms of disease. This atlas has been developed as an aid to pathologists and other biomedical scientists for identification of abnormalities in the developing murine urinary tract by cataloguing normal structures at each stage of development. Hematoxylin and eosin- and immunohistochemical-stained sections are provided, with a focus on E10.5-E18.5, as well as a brief discussion of postnatal events in urinary tract development. A section on abnormalities in the development of the urinary tract is also provided, and molecular mechanisms are presented as supplementary material. Additionally, overviews of the 2 key processes of kidney development, branching morphogenesis and nephrogenesis, are provided to aid in the understanding of the complex organogenesis of the kidney. One of the key findings of this atlas is the histological identification of the ureteric bud at E10.5, as previous literature has provided conflicting reports on the initial point of budding. Furthermore, attention is paid to points where murine development is significantly distinct from human development, namely, in the cessation of nephrogenesis.

Analysis of testosterone pathway genes in dogs (78,XY; SRY-positive) with ambiguous external genitalia revealed a homozygous animal for 2-bp deletion causing premature stop codon in HSD17B3

The genetic background of disorders of sex development (DSD) in dogs with a normal male sex chromosome set (78,XY) is poorly described. In this study, we present for the first time, an analysis of six genes of the testosterone pathway, encoding enzymes (CYP17A1, HSD3B2, HSD17B3, SRD5A2) and transcription factors (NR5A1, AR). The entire coding sequence and flanking regions of the introns, 5'-UTR and 3'-UTR were analyzed in five DSD dogs (78,XY, SRY-positive) with ambiguous external genitalia and in 15 control dogs. A homozygous deletion of 2 bp in exon 2 of HSD17B3 (hydroxysteroid 17-beta dehydrogenase 3) was found in a Dachshund dog with enlarged clitoris, vulva and abdominal gonads and decreased serum testosterone level. In silico analysis revealed that this deleterious variant causes truncation of the encoded polypeptide (from 306 to 65 amino acids) and deprivation of the active site of the encoded enzyme. Genotyping of 23 control Dachshund dogs showed a normal homozygous genotype. Thus, we assumed that the 2-bp deletion is the causative variant. Moreover, 24 SNPs (four in CYP17A1, three in HSD3B2, six in HSD17B3, five in SRD5A2, one in AR and five in NR5A1), two intronic indels (one in HSD3B2 and one in SRD5A2) and two microsatellite polymorphisms in exon 1 of AR were found. Six SNPs appeared to be novel. No association with DSD phenotype was observed. Identification of the first case of DSD in domestic animals caused by a deleterious variant of a gene involved in testosterone synthesis showed that these genes are important candidates in such studies.

A critical role for estrogen signaling in penis development

Hypospadias, a developmental defect of the penis, is one of the most common congenital malformations in humans. Its incidence has rapidly increased over recent decades, and this has been largely attributed to our increased exposure to endocrine-disrupting chemicals. Penis development is primarily an androgen-driven process; however, estrogen and xenoestrogens are known to affect penis development in both humans and mice. Here, we investigated the role of estrogen in the developing penis. Using a novel penis culture system, we showed that exogenous estrogen directly targets the developing penis in utero to cause hypospadias. In addition, we also uncovered an unexpected endogenous role for estrogen in normal postnatal penis development and showed that a loss of estrogen signaling results in a mild hypospadias phenotype, the most common manifestation of this disease in humans. Our findings demonstrated that both androgen and estrogen signaling are intrinsically required for normal urethral closure. These findings confirmed that penis development is not an entirely androgen-driven process but one in which endogenous estrogen signaling also plays a critical role.-Govers, L. C., Phillips, T. R., Mattiske, D. M., Rashoo, N., Black, J. R., Sinclair, A., Baskin, L. S., Risbridger, G. P., Pask, A. J. A critical role for estrogen signaling in penis development.

Identification of gene variants in 130 Han Chinese patients with hypospadias by targeted next-generation sequencing

Background

Hypospadias is a common congenital malformation of male external genitalia, which mainly manifests as an abnormal urethral opening on the ventral side of the penis. The etiology and clinical phenotype of hypospadias is highly heterogeneous, and its clinical diagnosis is challenging. Currently, over 70% of patients have an unknown etiology. Here, we performed a targeted analysis of gene mutations in 130 patients with hypospadias of unknown etiology to find the precise genetic cause.

Methods

We developed a targeted next‐generation sequencing (NGS) panel, encompassing the exon coding regions of 105 genes involved in external genitalia and urogenital tract development and performed sequencing analysis on 130 children with hypospadias of unknown etiology.

Results

In total, 25 patients with hypospadias (19.2%) were found to have 20 mutations among the nine genes involved in external genitalia and urogenital tract development, including 16 reported and four novel mutation sites. Twenty‐two patients (16.9%) had diagnostic variants. Multiple genetic mutations were identified in three of the 25 patients. Hypospadias combined with micropenis was the most common phenotype (68%) in 25 patients.

Conclusions

Higher frequency mutations were identified in SRD5A2 (52%) and AR (24%) in our patient cohort. Middle or posterior hypospadias with micropenis may be significant indicators of genetic variations. Polygenic inheritance may be a rare genetic cause of hypospadias.

Functional Characterization of Two New Variants in the Bone Morphogenetic Protein 7 Prodomain in Two Pairs of Monozygotic Twins With Hypospadias

Context

Variants in bone morphogenetic protein 7 (BMP7) have been reported in patients with hypospadias. Here we report and analyze two variants in the BMP7 prodomain in monozygotic twins with hypospadias.

Materials and Methods

Patients with hypospadias were prospectively recruited. After informed consent was obtained, DNA was extracted from blood. The coding regions of 1034 genes [including 64 known diagnostic genes and candidate genes for disorder/difference of sex development (DSD)] were sequenced using a targeted capture approach (HaloPlex, Agilent, Santa Clara, CA), combined with massively parallel sequencing. The resulting variants were filtered for rarity in the general population (<1%) and in our screen. Quality, depth of the reads, and predicted pathogenicity were also considered. The consequences of the identified mutations on BMP7 expression was determined by Western blot analysis on culture media from transfected cells, and activity measured using a SMAD 1/5-responsiveness luciferase assay.

Results

We analyzed DNA from 46 patients with hypospadias. Two variants in BMP7 were identified in two pairs of monozygotic concordant twins exhibiting proximal hypospadias. Both variants are heterozygous, nonsynonymous, and affect highly conserved amino acids in the prodomain of BMP7 in regions predicted to be important for BMP7 assembly/folding. Functional analyses demonstrated that both variants disrupt BMP7 synthesis or secretion.

Conclusion

Through our targeted DSD panel we have identified two variants in the prodomain of BMP7 in hypospadias. By decreasing BMP7 synthesis, these variants are likely to limit BMP7 bioavailability during closure of the urethral plate.Further analysis of patients with hypospadias may uncover additional variants that cause this DSD.

Use of ondansetron during pregnancy and the risk of major congenital malformations: A systematic review and meta-analysis

AIMS

To investigate whether ondansetron use during pregnancy is associated with increased rates of major or subgroups of malformations.

METHODS

PubMed/MEDLINE, Cochrane and Reprotox^® databases were searched. Observational studies comprising an exposed and control group (healthy and/or disease-matched) were included.

RESULTS

No significant increased risk for major malformations, heart defects, orofacial clefts, genitourinary malformations or hypospadias were identified in our primary analysis. A significant heterogeneity existed for isolated cleft palate. Elevated point estimates and altered statistical significances were present for some of the outcomes among secondary analyses.

CONCLUSIONS

Ondansetron use during pregnancy was not associated with a significant increase in rate of major or selected subgroups of malformations in our primary analysis. However, results of the secondary analyses warrant the need for continued surveillance. These results may be reassuring for pregnant women in whom ondansetron use is clinically indicated since the absolute risks of possible concerns appear to be low.

The external genitalia in juvenile Caiman latirostris differ in hormone sex determinate-female from temperature sex determinate-female

The broad-snouted caiman (Caiman latirostris) is a crocodilian species that inhabits South American wetlands. As in all other crocodilians, the egg incubation temperature during a critical thermo-sensitive window (TSW) determines the sex of the hatchlings, a phenomenon known as temperature-dependent sex determination (TSD). In C. latirostris, we have shown that administration of 17-β-estradiol (E₂) during the TSW overrides the effect of the male-producing temperature, producing phenotypic females (E₂SD-females). Moreover, the administration of E₂ during TSW has been proposed as an alternative way to improve the recovery of endangered reptile species, by skewing the population sex ratio to one that favors females. However, the ovaries of E₂SD-female caimans differ from those of TSD-females. In crocodilians, the external genitalia (i.e. clitero-penis structure or phallus) are sexually dimorphic and hormone-sensitive. Despite some morphological descriptions aimed to facilitate sexing, we found no available data on the C. latirostris phallus histoarchitecture or hormone dependence. Thus, the aims of this study were: (1) to establish the temporal growth pattern of the phallus in male and female caimans; (2) to evaluate histo-morphological features and the expression of estrogen receptor alpha (ERα) and androgen receptor (AR) in the phallus of male and female pre-pubertal juvenile caimans; and (3) to determine whether the phallus of TSD-females differs from the phallus of E₂SD-females. Our results demonstrated sexually dimorphic differences in the size and growth dynamics of the caiman external genitalia, similarities in the shape and spatial distribution of general histo-morphological compartments, and sexually dimorphic differences in innervation, smooth muscle fiber distribution, collagen organization, and ERα and AR expressions. The external genitalia of E₂SD-females differed from that of TSD-females in many histological features and in the expression of ERα and AR, resembling patterns described in males. Our results alert on the effects of estrogen agonist exposure during TSW and suggest that caution must be taken regarding the use of E₂SD as a procedure for wildlife population management.

Dydrogesterone: pharmacological profile and mechanism of action as luteal phase support in assisted reproduction

The pharmacological and physiological profiles of progestogens used for luteal phase support during assisted reproductive technology are likely to be important in guiding clinical choice towards the most appropriate treatment option. Various micronized progesterone formulations with differing pharmacological profiles have been investigated for several purposes. Dydrogesterone, a stereoisomer of progesterone, is available in an oral form with high oral bioavailability; it has been used to treat a variety of conditions related to progesterone deficiency since the 1960s and has recently been approved for luteal phase support as part of an assisted reproductive technology treatment. The primary objective of this review is to critically analyse the clinical implications of the pharmacological and physiological properties of dydrogesterone for its uses in luteal phase support and in early pregnancy.

The genetic factors contributing to hypospadias and their clinical utility in its diagnosis

Hypospadias is among the most common congenital malformations in male neonates. It results from abnormal penile and urethral development, but is a multifactorial disorder that is highly heterogeneous, with several genetic and environmental determinants. Monogenic and chromosomal abnormalities are present in approximately 30% of cases, although the genetic factors contributing to hypospadias remain unknown in 70% of cases. While defects in androgen synthesis can lead to this malformation, mutational analyses have shown several genes, such as sonic hedgehog, fibroblast growth factors, bone morphogenetic proteins, homeobox genes, and the Wnt family, are involved in the normal development of male external genitalia. Mutations in the genes of penile development (e.g., HOX, FGF, Shh) and testicular determination (e.g., WT1, SRY), luteinizing hormone receptor, and androgen receptor have also been proposed to be implicated in hypospadias. Here we review the recent advances in this field and discuss the potential genes that could determine the risk of hypospadias.

Macroscopic whole-mounts of the developing human fetal urogenital-genital tract: Indifferent stage to male and female differentiation

We present a detailed review of fetal development of the male and female human urogenital tract from 8 to 22 weeks gestation at the macroscopic and morphometric levels. Human fetal specimens were sexed based on macroscopic identification of fetal testes or ovaries, Wolffian or Müllerian structures and the presence of the SRY gene in the specimens at or near the indifferent stage (8-9 weeks). Specimens were photographed using a dissecting microscope with transmitted and reflected light. Morphometric measurements were taken of each urogenital organ. During this time period, development of the male and female urogenital tracts proceeded from the indifferent stage to differentiated organs. The kidneys, ureters, and bladder developed identically, irrespective of sex with the same physical dimensions and morphologic appearance. The penis, prostate and testis developed in males and the clitoris, uterus and ovary in females. Androgen-dependent growth certainly influenced size and morphology of the penile urethra and prostate, however, androgen-independent growth also accounted for substantial growth in the fetal urogenital tract including the clitoris.

CYP17 gene plays a key role in goose genital growth by influencing the testosterone level at puberty

All birds reproduce by internal fertilization, but only 3% of birds have external genitalia. Hormone secretions and body size influence genital growth, but the actual regulatory mechanism is rarely reported. Thus, using 35 geese as experimental material, the regulatory mechanism of goose external genitalia growth was explored by measuring body size parameters, serum hormone concentrations, and related gene expression. In this study, genital growth was different among tested geese, but histological and morphological results showed that all geese external genitalia contained complete tissues. Measurements of hormone levels showed that at puberty, as the genital length increased, irregular decreases were observed in the levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), whereas an irregular increase was observed in the levels of testosterone (T); furthermore, the levels of testosterone (T) gradually increased to a peak at 34 weeks. Based on RT-PCR results, as the genital length increased, only the expression of 17α-hydroxylase/17, 20-lyase (CYP17) mRNA slightly decreased at first, and then significantly increased to a peak, whereas the expression patterns of other genes were irregular. Furthermore, the CYP17 immunohistochemistry results also showed a pattern that was highly consistent with the patterns of mRNA expression and T secretion. In addition, based on body measurements, as body weight increased, the genital length increased. Thus, these results suggested that the CYP17 gene plays a key role in goose genital growth.

Development of the human penis and clitoris

The human penis and clitoris develop from the ambisexual genital tubercle. To compare and contrast the development of human penis and clitoris, we used macroscopic photography, optical projection tomography, light sheet microscopy, scanning electron microscopy, histology and immunohistochemistry. The human genital tubercle differentiates into a penis under the influence of androgens forming a tubular urethra that develops by canalization of the urethral plate to form a wide diamond-shaped urethral groove (opening zipper) whose edges (urethral folds) fuse in the midline (closing zipper). In contrast, in females, without the influence of androgens, the vestibular plate (homologue of the urethral plate) undergoes canalization to form a wide vestibular groove whose edges (vestibular folds) remain unfused, ultimately forming the labia minora defining the vaginal vestibule. The neurovascular anatomy is similar in both the developing human penis and clitoris and is the key to successful surgical reconstructions.