Sexual Development最新文献

Introduction: Needlefish (Belonidae family) comprises 44 known species distributed worldwide. These species are predominantly marine but include estuarine representatives and 12 freshwater species. Among the recognized species, eight are endemic to South American rivers. Cytogenetic studies of Belonidae are scarce and mostly limited to describing the diploid chromosome number (2n) and karyotypic structure.

Methods: We used classical and molecular cytogenetic markers to karyotypically characterize Pseudotylosurus microps to understand the evolutionary processes of Belonidae species in the Amazon basin.

Results: P. microps exhibited different diploid numbers between males (2n=47, 3m+3sm+41st/a FN=53) and females (2n=48, 4m+4sm+40st/a FN=56). Our study revealed the first case of multiple sex chromosomes in the Belonidae family.

Conclusions: These findings describe a multiple sex chromosome system of the type X1X1X2X2/X1X2Y. The C-banding pattern and 5S rDNA mapping suggest that this system likely resulted from a tandem fusion between a homolog of pair 1 and a homolog of pair 3, producing a large acrocentric Y chromosome. We propose that karyotypic changes due to internal chromosomal rearrangements, as observed in P. microps, can lead to species diversification and, in some cases, the emergence of a heteromorphic and multiple sex chromosome system.

Recent studies have demonstrated that the production of bidirectional enhancer-derived transcripts (eRNAs) is a characteristic of an active Cis-regulatory element (CRE). Higher levels of eRNA synthesis correlate with the activation of histone modifications, a potentially valuable tool for deciphering the complexity of the gene regulatory network. To understand the changes of CREs during gonadal development in mice, we collected gonadal WT1-positive cells from the piggyBac-Wt1-mCherry-2A-EGFP (PBWt1-RG) reporter strain at E13.5, E16.5, and P0 in both sexes and conducted Cap Analysis of Gene Expression analysis (CAGE) which is capable to capture transcriptional starting site (TSS). We compared the levels of intergenic bidirectional RNA, i.e, potentially eRNA, according to sex at each stage (testis somatic cells vs ovary somatic cells at E13.5, E16.5, and P0) and stage in each sex (E13.5 vs E16.5, E16.5 vs P0, and E13.5 vs P0 in testis somatic cells or ovary somatic cells). Intergenic RNAs with significant changes (|Log2FC| > 1, p < 0.05) were selected. The TSS profile of intergenic RNA changed more profoundly in testis somatic cells than in ovary somatic cells, suggesting embryonic testicular development is driven by larger changes in a transcriptional regulatory network than ovarian development. Based on the profiles of the predicted transcription factors (TFs) that would bind to the active CREs during gonadal development, the NR4A, EGR, and TCF3 families would be novel TFs to play pivotal roles in gonadal development. Identifying active CREs using eRNAs would provide a means to comprehensively understand the transcriptional regulatory system, leading to valuable insights into the gonadal development of male and female individuals.

Introduction: Explicit outcomes routinely measured across the life span following hypospadias surgery, defined by a core outcome set (COS), will harmonize and overcome reporting heterogeneity.

Methods: Age-specific outcomes identified in a literature review were presented in a three-round Delphi survey. Participants (professionals, parents, and patients) were encouraged to suggest outcomes in the first Delphi round. In subsequent rounds, participants were asked to choose and rank up to five preferred outcomes for each age. To be deemed core, an outcome needed over 70% of votes in a round.

Results: Professionals were mainly paediatric urologists (rounds 1, 2, 3: n = 57 [77%], 39 [78%], 35 [81%]). The response rates from parents/patients (rounds 1, 2, 3: n = 17, 5, 3) were low. In young boys (<6 years, 10-11 years), four core outcomes were identical (voiding, fistula, re-operation, and urethral stricture). Core outcomes in boys aged 11-16 years (cosmesis, curvature, voiding, stricture, and psychosocial status) and boys >16 years (cosmesis, curvature, erection, voiding, and psychosexual development) varied more.

Conclusion: Outcomes to include in a COS were consistent in younger boys. A larger variety was observed in older boys and reflects less clarity on relevant outcomes.

Background: Sex chromosomes evolve from an autosomal pair after the acquisition of a sex-determining gene. The primary sex chromosomes are homomorphic in both sexes and often undergo heteromorphism in either sex (XY in males or ZW in females) in association with chromosome rearrangements such as inversion, which creates a non-recombining region, called a stratum. Then, multiple strata may form by sequential inversions and extend the non-recombining region, where gene divergence accelerates, and degeneration of the Y or W chromosome progressively occurs.

Summary: In contrast to the conventional theory, we propose a shortcut in heteromorphic sex chromosome evolution, where an autosomal pair directly evolves into a heteromorphic sex chromosome pair. We illustrate this with two frog cases where Y chromosome or autosome, which is morphologically inverted, was introgressed from another species through interspecific hybridization, instantly forming a new heteromorphic sex chromosome pair. This event resulted in a distinct non-recombining region immediately after hybridization.

Key messages: The introduction of an inverted chromosome from a different species may be associated with benefits in morphology, breeding behavior, hybrid viability, sex determination, and recovery of the sex ratio of the hybrids. We discuss the molecular mechanisms driving preferential mutations in the introduced, inverted chromosome through interspecific hybridization.

Background: Canine cryptorchidism, manifested by an abnormal testicular position, poses significant health risks and reproductive challenges in affected males. Despite a high prevalence, estimated at up to 10% in the canine population, a comprehensive understanding of its pathogenesis remains elusive. Studies in human cryptorchids and knockout mice have identified key factors involved in testicular descent, including INSL3, RXFP2, and AR. To date, only three DNA variants, found in the RXFP2, HMGA2, and KAT6A genes, have been associated with canine cryptorchidism.

Summary: This review briefly summarizes current knowledge on testicular descent and the factors that regulate this process, based on cryptorchidism in humans and mice. It also highlights recent findings related to canine cryptorchidism, focusing on the INSL3, HMGA2, and KAT6A genes. The most significant results are discussed, with an emphasis on the role of the epididymis in testicular descent. This report presents insights that may facilitate further research aiming to broaden our understanding of canine cryptorchidism pathogenesis.

Key messages: DNA polymorphism in the KAT6A gene, associated with changes in global H3K9 acetylation, as well as the DNA methylation pattern in the INSL3 gene, suggest that further research should strongly focus on epigenetic modifications. In addition, the development of the epididymo-testicular junction and the link between cryptorchidism prevalence and dog size should be further investigated.

Introduction: The MAPK genes are critical for gonadal differentiation in eutherian mammals, but their role in marsupial mammals is unknown. Characterisation and phylogenetic analyses of the tammar wallaby MAPK genes show these genes are highly conserved with their orthologues in mammalian and non-mammalian species.

Methods: We cultured sexually indifferent tammar gonads in the presence of p38α and -β MAPK inhibitor, SB202190.

Results: SB202190 downregulated SOX9 and AMH levels in XY-treated gonads when compared to controls, similar to the effects of oestrogen on the MAPK pathway in males. In contrast, XX gonads treated with the SB202190 inhibitor showed no change in mRNA expression between the control and treated gonads for any of the markers tested.

Conclusions: This study confirms that components of the MAPK pathway drive testis differentiation via the key downstream genes SOX9 and AMH in marsupials as is observed in eutherian mammals.

Introduction: Hydrocolpos, a rare condition characterized by cystic dilatation of the vagina, can arise from various etiologies, including isolated imperforate hymen and vaginal atresia. Genetic conditions, such as Bardet-Biedl syndrome (BBS), may also manifest with hydrocolpos as part of urogenital malformations.

Methods: We present a case of neonatal hydrocolpos associated with BBS. Sequencing of 19 BBS genes was performed to elucidate the genetic basis of the syndrome.

Results: Genetic analysis revealed a novel frameshift indel variant (c.1543_1546dup p.Thr516Argfs*7) in the BBS10 gene. This finding expands the spectrum of BBS mutations and underscores the importance of genetic evaluation in patients with hydrocolpos, particularly when associated with additional clinical features suggestive of syndromic etiology.

Conclusion: Pediatric urologists should maintain a high index of suspicion for underlying genetic conditions, including BBS, in neonates presenting with hydrocolpos, given the potential for more severe associated complications such as renal and retinal diseases, obesity, and polydactyly.

Introduction: The presence of Y-chromosomal material in females with Turner syndrome (TS) is a well-established risk factor for developing gonadoblastoma and malignant transformations thereof. However, these events are rarely seen in TS patients with no Y-chromosomal material. Thus, it is the current understanding that parts of the Y-chromosome are essential for the malignant transformation of gonadoblastoma in the dysgenetic gonad.

Methods: We report a case of a TS female with an apparent 46,X,idic(Xq) karyotype, who was diagnosed with a metastatic dysgerminoma. Whole exome sequencing of the tumor and blood, along with RNA sequencing of the tumor, was performed to comprehensively search for cryptic Y-chromosomal material and pathogenic variants.

Results: No Y-chromosomal material was detected in either tumor or blood. Whole exome-sequencing of DNA and RNA revealed a pathogenic somatic gain-of-function mutation in KIT and a pathogenic missense mutation in MTOR. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy, followed by adjuvant chemotherapy. Unfortunately, she died due to chemotherapy-induced pneumonitis 7 months after the initial diagnosis.

Conclusion: Females with TS can develop metastatic dysgerminoma even in the absence of Y-chromosomal material. This questions the current understanding of Y-chromosomal material being essential for the malignant transformation of a gonadoblastoma in the dysgenetic gonad.