Genetics of Disorders of Sex Development: The DSD-TRN Experience

Role of the pediatrician in the initial management of a newborn with Differences of Sex Development or hypospadias

Caring for newborns with atypical genitalia presents significant challenges. With advancements in prenatal imaging and genetic testing, differences of sex development (DSD) diagnoses are increasingly made before birth through ultrasound and genetic testing, offering opportunities to optimally prepare parents for the birth of their child. Although guidelines recommend management in a specialized DSD center, most newborns who have a DSD are born in settings without immediate access to such expertise. Consequently, local healthcare professionals play a crucial role in the initial assessment, communication, and parental support. This document provides a structured approach to conduct a comprehensive physical examination, evaluate the external genitalia, and initiate appropriate biochemical, hormonal and genetic investigations. Clear, neutral, and supportive language is essential when communicating with parents and has been shown to improve outcomes.

CONCLUSION

A structured clinical approach, early consultation with an expert DSD team, and clear, compassionate communication with the parents are key for the initial management of babies born with a DSD and their parents.

WHAT IS KNOWN

• Differences in sex development (DSD) are rare, complex congenital conditions that often present with atypical genitalia in newborns, requiring early specialized care from a multidisciplinary team. • International and regional guidelines have been developed for the multidisciplinary management of DSD to improve the quality of care.

WHAT IS NEW

• This article offers practical and structured guidance for pediatricians on the initial management of newborns suspected of having Disorders of Sex Development (DSD), both before and after birth. • It emphasizes the significance of a systematic clinical approach, early consultation with experts, and effective communication with parents.

Oligogenic analysis across broad phenotypes of 46,XY differences in sex development associated with NR5A1/SF-1 variants: findings from the international SF1next study

BACKGROUND

Oligogenic inheritance has been suggested as a possible mechanism to explain the broad phenotype observed in individuals with differences of sex development (DSD) harbouring NR5A1/SF-1 variants.

METHODS

We investigated genetic patterns of possible oligogenicity in a cohort of 30 individuals with NR5A1/SF-1 variants and 46,XY DSD recruited from the international SF1next study, using whole exome sequencing (WES) on family trios whenever available. WES data were analysed using a tailored filtering algorithm designed to identify rare variants in DSD and SF-1-related genes. Identified variants were subsequently tested using the Oligogenic Resource for Variant Analysis (ORVAL) bioinformatics platform for a possible combined pathogenicity with the individual NR5A1/SF-1 variant.

FINDINGS

In 73% (22/30) of the individuals with NR5A1/SF-1 related 46,XY DSD, we identified one to seven additional variants, predominantly in known DSD-related genes, that might contribute to the phenotype. We found identical variants in eight unrelated individuals with DSD in DSD-related genes (e.g., TBCE, FLNB, GLI3 and PDGFRA) and different variants in eight genes frequently associated with DSD (e.g., CDH23, FLNB, GLI2, KAT6B, MYO7A, PKD1, SPRY4 and ZFPM2) in 15 index cases. Our study also identified combinations with NR5A1/SF-1 variants and variants in novel candidate genes.

INTERPRETATION

These findings highlight the complex genetic landscape of DSD associated with NR5A1/SF-1, where in several cases, the use of advanced genetic testing and filtering with specific algorithms and machine learning tools revealed additional genetic hits that may contribute to the phenotype.

FUNDING

Swiss National Science Foundation and Boveri Foundation Zurich.

Long-read sequencing resolves the clinically relevant CYP21A2 locus, supporting a new clinical test for Congenital Adrenal Hyperplasia

Congenital Adrenal Hyperplasia (CAH), one of the most common inherited disorders, is caused by defects in adrenal steroidogenesis. It is potentially lethal if untreated and is associated with multiple comorbidities, including fertility issues, obesity, insulin resistance, and dyslipidemia. CAH can result from variants in multiple genes, but the most frequent cause is deletions and conversions in the segmentally duplicated RCCX module, which contains the CYP21A2 gene and a pseudogene. The molecular genetic test to identify pathogenic alleles is cumbersome, incomplete, and available from a limited number of laboratories. It requires testing parents for accurate interpretation, leading to healthcare inequity. Less severe forms are frequently misdiagnosed, and phenotype/genotype correlations incompletely understood. We explored whether emerging technologies could be leveraged to identify all pathogenic alleles of CAH, including phasing in proband-only cases. We targeted long-read sequencing outputs that would be practical in a clinical laboratory setting. Both HiFi-based and nanopore-based whole-genome long-read sequencing datasets could be mined to accurately identify pathogenic single-nucleotide variants, full gene deletions, fusions creating non-functional hybrids between the gene and pseudogene ("30-kb deletion"), as well as count the number of RCCX modules and phase the resulting multimodular haplotypes. On the Hi-Fi data set of 6 samples, the PacBio Paraphase tool was able to distinguish nine different mono-, bi-, and tri-modular haplotypes, as well as the 30-kb and whole gene deletions. To do the same on the ONT-Nanopore dataset, we designed a tool, Parakit, which creates an enriched local pangenome to represent known haplotype assemblies and map ClinVar pathogenic variants and fusions onto them. With few labels in the region, optical genome mapping was not able to reliably resolve module counts or fusions, although designing a tool to mine the dataset specifically for this region may allow doing so in the future. Both sequencing techniques yielded congruent results, matching clinically identified variants, and offered additional information above the clinical test, including phasing, count of RCCX modules, and status of the other module genes, all of which may be of clinical relevance. Thus long-read sequencing could be used to identify variants causing multiple forms of CAH in a single test.

Genomic testing for differences of sex development: Practices and perceptions of clinicians

OBJECTIVES

To investigate the approach taken by clinicians involved in the diagnosis and management of individuals with Differences of Sex Development (DSD), particularly with regard to genomic testing, and identify perceived gaps/strengths/barriers in current practice.

DESIGN AND METHODS

An anonymous online survey was developed, with questions exploring demographics, perceptions of genomic testing, availability of genetics services and opinions on the role and utility of genomic testing in DSD. All responses were anonymous. Clinicians involved in the diagnosis and management of individuals with DSD were recruited from relevant societies and departments across Australia and New Zealand.

RESULTS

79 eligible clinicians commenced the survey, with 63 completing it and 16 providing a partial response. The perceived benefit of having a genetic diagnosis for DSD was almost unanimous (97%). Almost half (48%) of respondents reported barriers in genomic testing. 81% of respondents reported they order genomic tests currently. Approaches to genomic testing when faced with four different clinical scenarios varied across respondents. Clinicians perceived genomic testing to be underutilised (median 36 on sliding scale from 0 to 100).

CONCLUSIONS

Despite 97% of respondents reporting benefit of a genetic diagnosis for individuals with DSD, this was not reflected throughout the survey with regard to clinical implementation. When faced with clinical scenarios, the recommendations for genomic testing from respondents was much lower, indicating the discrepancy between perception and clinical practice. Genomic testing in the context of DSD is seen as both beneficial and desired, yet there are multiple barriers impacting its integration into standard clinical care.

DSD-related attitudes and beliefs held by pediatric endocrinologists and urologists: Insights from the North American disorders/differences of sex development (DSD) clinician survey

BACKGROUND

Disorders/Differences of Sex Development (DSD) encompass congenital conditions with atypical development of chromosomal, gonadal, or anatomical sex. Due to the rarity and complexity of these conditions, strong evidence for clinical practices is scarce, leading to controversies in management.

OBJECTIVE

This study, part of a broader project, examines changes over time in the attitudes and beliefs of DSD healthcare providers, focusing on factors contributing to patients' life satisfaction and the influence of medical specialty, gender, and age.

METHODS

Participants included active members of the Pediatric Endocrine Society (PES) and the Societies for Pediatric Urology (SPU) at three time points: 2003-2004 (T1), 2010-2011 (T2), and 2020 (T3). A survey covering predictors of patient life satisfaction, attitudes and beliefs regarding DSD care and outcomes, and participant characteristics was administered. Data were analyzed using descriptive statistics and Generalized Estimating Equations (GEE).

RESULTS

Demographics: Participation rates were 56% (PES) and 64.7% (SPU) at T1, 41.1% (PES) and 52.3% (SPU) at T2, and 25.6% (PES) and 51.2% (SPU) at T3. Most participants were male (T1: 70.6%, T2: 61.7%, T3: 70.6%). Factors Affecting Life Satisfaction: Both endocrinologists and urologists ranked "gender identity consistent with assigned sex" as most important. Over time, the endorsement of some factors, such as performing genital surgery at Centers of Excellence, increased, while others, like the influence of prenatal androgen exposure determining gender identity, varied by specialty and gender. Attitudes and Beliefs: Across 18 statements, responses indicated three clusters with strong agreement, moderate agreement, and strong disagreement. Statements on the importance of family background and avoiding gender discordance were consistently endorsed, while those on delaying hypospadias repair until consent were least endorsed.

DISCUSSION

The study highlights variability in beliefs about DSD management over time, influenced by specialty, gender, and age. Despite consensus on some care principles, discrepancies remain, particularly regarding the impact of prenatal androgens and the timing of surgical interventions. These findings underscore the need for regular interdisciplinary communication to align clinical practices with evidence-based guidelines and address subjective beliefs.

CONCLUSION

The survey illustrates evolving perspectives among DSD healthcare providers, emphasizing the need for continued dialogue and education to bridge gaps between clinical evidence and practice. Collaborative efforts, such as the international I-DSD and the U.S. DSD Translational Research Network, are crucial for advancing patient-centered care in this field.

Defining Success in the Delivery of Fertility-Related Care for Patients with Differences of Sex Development

INTRODUCTION

Individuals with differences of sex development (DSD) experience complex, often competing, medical and psychosocial challenges surrounding fertility. The study aimed to characterize how "success" in fertility-related care is conceptualized and attained among individuals with a DSD, their parents or caregivers, healthcare providers, and other stakeholders.

METHODS

As part of a larger study, DSD stakeholders (n = 110) participated in semi-structured interviews covering the clinical care of patients with DSD. Primary questions included "What is a successful outcome in DSD care?" and "How do you achieve it?" with fertility as either a spontaneous or suggested topic of discussion. Transcripts were analyzed utilizing a phenomenological approach. This analysis focuses on the extracted themes related to fertility.

RESULTS

Fertility was discussed by 19/24 individuals with DSD, 12/19 parents or caregivers, 35/37 healthcare providers, and 19/30 other stakeholders. Components of successful fertility-related care included (1) specific discussions surrounding the relationship between DSD and fertility potential, options for fertility preservation, and options for non-biologic parenthood; (2) early and repeated introduction of these topics; and (3) consideration of age, developmental maturity, and cultural context on decisions around fertility. Challenges included the lack of fertility outcome data in this population and the irreversibility of gonadectomy. Trade-offs identified included anatomic typicality versus function, fertility preservation versus cancer risk reduction, and balancing the different priorities of stakeholders.

DISCUSSION/CONCLUSIONS

A wide range of DSD stakeholders highlighted the importance of addressing fertility concerns in achieving favorable outcomes for individuals with DSD. These stakeholder perspectives should inform fertility-related education, shared decision-making processes, and clinical care.

Reprograming skin fibroblasts into Sertoli cells: a patient-specific tool to understand effects of genetic variants on gonadal development

BACKGROUND

Disorders/differences of sex development (DSD) are congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical. With overlapping phenotypes and multiple genes involved, poor diagnostic yields are achieved for many of these conditions. The current DSD diagnostic regimen can be augmented by investigating transcriptome/proteome in vivo, but it is hampered by the unavailability of affected gonadal tissue at the relevant developmental stage. We try to mitigate this limitation by reprogramming readily available skin tissue-derived dermal fibroblasts into Sertoli cells (SC), which could then be deployed for different diagnostic strategies. SCs form the target cell type of choice because they act like an organizing center of embryonic gonadal development and many DSD arise when these developmental processes go awry.

METHODS

We employed a computational predictive algorithm for cell conversions called Mogrify to predict the transcription factors (TFs) required for direct reprogramming of human dermal fibroblasts into SCs. We established trans-differentiation culture conditions where stable transgenic expression of these TFs was achieved in 46, XY adult dermal fibroblasts using lentiviral vectors. The resulting Sertoli like cells (SLCs) were validated for SC phenotype using several approaches.

RESULTS

SLCs exhibited Sertoli-like morphological and cellular properties as revealed by morphometry and xCelligence cell behavior assays. They also showed Sertoli-specific expression of molecular markers such as SOX9, PTGDS, BMP4, or DMRT1 as revealed by IF imaging, RNAseq and qPCR. The SLC transcriptome shared about two thirds of its differentially expressed genes with a human adult SC transcriptome and expressed markers typical of embryonic SCs. Notably, SLCs lacked expression of most markers of other gonadal cell types such as Leydig, germ, peritubular myoid or granulosa cells.

CONCLUSIONS

The trans-differentiation method was applied to a variety of commercially available 46, XY fibroblasts derived from patients with DSD and to a 46, XX cell line. The DSD SLCs displayed altered levels of trans-differentiation in comparison to normal 46, XY-derived SLCs, thus showcasing the robustness of this new trans-differentiation model. Future applications could include using the SLCs to improve definitive diagnosis of DSD in patients with variants of unknown significance.

A massive alteration of gene expression in undescended testicles of dogs and the association of KAT6A variants with cryptorchidism

Cryptorchidism is the most common form of disorder of sex development in male dogs, but its hereditary predisposition is poorly elucidated. The gonadal transcriptome of nine unilaterally cryptorchid dogs and seven control dogs was analyzed using RNA-seq. Comparison between the scrotal and inguinal gonads of unilateral cryptorchid dogs revealed 8,028 differentially expressed genes (DEGs) (3,377 up-regulated and 4,651 down-regulated). A similar number of DEGs (7,619) was found by comparing the undescended testicles with the descended testicles of the control dogs. The methylation status of the selected DEGs was also analyzed, with three out of nine studied DEGs showing altered patterns. Bioinformatic analysis of the cDNA sequences revealed 20,366 SNP variants, six of which showed significant differences in allelic counts between cryptorchid and control dogs. Validation studies in larger cohorts of cryptorchid (n = 122) and control (n = 173) dogs showed that the TT genotype (rs850666472, p.Ala1230Val) and the AA genotype in 3'UTR (16:23716202G>A) in KATA6, responsible for acetylation of lysine 9 in histone H3, are associated with cryptorchidism (P = 0.0383). Both the transcript level of KAT6A and H3K9 acetylation were lower in undescended testes, and additionally, the acetylation depended on the genotypes in exon 17 and the 3'UTR. Our study showed that the massive alteration of the transcriptome in undescended testicles is not caused by germinal DNA variants in DEG regulatory sequences but is partly associated with an aberrant DNA methylation and H3K9 acetylation patterns. Moreover, variants of KAT6A can be considered markers associated with the risk of this disorder.

Clinical and genetic characteristics of a large international cohort of individuals with rare NR5A1/SF-1 variants of sex development

BACKGROUND

Steroidogenic factor 1 (SF-1/NR5A1) is essential for human sex development. Heterozygous NR5A1/SF-1 variants manifest with a broad range of phenotypes of differences of sex development (DSD), which remain unexplained.

METHODS

We conducted a retrospective analysis on the so far largest international cohort of individuals with NR5A1/SF-1 variants, identified through the I-DSD registry and a research network.

FINDINGS

Among 197 individuals with NR5A1/SF-1 variants, we confirmed diverse phenotypes. Over 70% of 46, XY individuals had a severe DSD phenotype, while 90% of 46, XX individuals had female-typical sex development. Close to 100 different novel and known NR5A1/SF-1 variants were identified, without specific hot spots. Additionally, likely disease-associated variants in other genes were reported in 32 individuals out of 128 tested (25%), particularly in those with severe or opposite sex DSD phenotypes. Interestingly, 48% of these variants were found in known DSD or SF-1 interacting genes, but no frequent gene-clusters were identified. Sex registration at birth varied, with <10% undergoing reassignment. Gonadectomy was performed in 30% and genital surgery in 58%. Associated organ anomalies were observed in 27% of individuals with a DSD, mainly concerning the spleen. Intrafamilial phenotypes also varied considerably.

INTERPRETATION

The observed phenotypic variability in individuals and families with NR5A1/SF-1 variants is large and remains unpredictable. It may often not be solely explained by the monogenic pathogenicity of the NR5A1/SF-1 variants but is likely influenced by additional genetic variants and as-yet-unknown factors.

FUNDING

Swiss National Science Foundation (320030-197725) and Boveri Foundation Zürich, Switzerland.

"It became easier once I knew": Stakeholder perspectives for educating children and teenagers about their difference of sex development

OBJECTIVE

Secrecy about a child's difference of sex development (DSD) can lead to internalized shame and stigma. We explored how teenagers and adults with DSD, parents, healthcare providers, and allied professionals value and perceive patient education.

METHODS

Stakeholders (n = 110) completed qualitative semi-structured interviews. Relevant themes for educational content were queried and organized.

RESULTS

Education was consistently identified as essential to successful outcomes. There was less consistency in how to educate patients. Disagreement existed regarding who should champion the education process. Participants believed medically relevant information should be shared gradually with attention to developmental capacity. Details were lacking regarding how much or what information to share. Participants noted that vetted resources were helpful. Benefits of sharing condition-specific information with patients included supporting their psychosocial development. Barriers included parental resistance to sharing information due to shame/stigma, and cultural and/or family dynamics.

CONCLUSIONS

Stakeholders' different perspectives regarding patient DSD education warrant future research to focus on the design, evaluation, and implementation of education-focused interventions.

PRACTICE IMPLICATIONS

Healthcare providers are responsible for supporting the education of children and teenagers with DSD about their condition. When considering barriers, adopting a cultural or family systems framework can reduce parental resistance and promote open dialogue.

Individuals with numerical and structural variations of sex chromosomes: interdisciplinary management with focus on fertility potential

Diagnosis and management of individuals who have differences of sex development (DSD) due to numerical or structural variations of sex chromosomes (NSVSC) remains challenging. Girls who have Turner syndrome (45X) may present with varying phenotypic features, from classical/severe to minor, and some remain undiagnosed. Boys and girls who have 45,X/46,XY chromosomal mosaicism may have Turner syndrome-like features and short stature; therefore, unexplained short stature during childhood requires karyotype analysis in both sexes, particularly if characteristic features or atypical genitalia are present. Many individuals with Klinefelter syndrome (47XXY) remain undiagnosed or are only diagnosed as adults due to fertility problems. Newborn screening by heel prick tests could potentially identify sex chromosome variations but would have ethical and financial implications, and in-depth cost-benefit analyses are needed before nationwide screening can be introduced. Most individuals who have NSVSC have lifelong co-morbidities and healthcare should be holistic, personalized and centralized, with a focus on information, psychosocial support and shared decision-making. Fertility potential should be assessed individually and discussed at an appropriate age. Oocyte or ovarian tissue cryopreservation is possible in some women who have Turner syndrome and live births have been reported following assisted reproductive technology (ART). Testicular sperm cell extraction (TESE) is possible in some men who have 45,X/46,XY mosaicism, but there is no established protocol and no reported fathering of children. Some men with Klinefelter syndrome can now father a child following TESE and ART, with multiple reports of healthy live births. Children who have NSVSC, their parents and DSD team members need to address possibilities and ethical questions relating to potential fertility preservation, with guidelines and international studies still needed.

Surgical Decision-Making for Individuals with Differences of Sex Development: Stakeholders' views

Introduction

Advocacy and human rights organizations have called for a moratorium on elective surgical procedures until the patient is able to fully participate in the decision-making process. Due to the controversial nature surrounding surgery in differences of sex development (DSD) care, we aimed to assess the factors that teens and adults with DSD, parents, healthcare providers and other allied professionals consider pertinent to complex surgical decisions in DSD.

Methods

Stakeholders (n=110) in DSD care participated in semi-structured interviews exploring features and potential determinants of successful healthcare outcomes. Audio-recordings were transcribed, coded, and analyzed using qualitative data software. Codes for "Process of Decision-Making" and "Successful Outcome-Surgery/Appearance/Function" were further searched using keywords "surgery," "procedure," and "timing."

Results

Several themes were identified: 1) The nature or type of the decision being made; 2) Who should be involved in the decision-making process; 3) Timing of conversations about surgery; 4) Barriers to decision-making surrounding surgery; 5) The elements of surgical decision-making; and 6) The optimal approach to surgical decision-making. Many stakeholders believed children and adolescents with DSD should be involved in the process as developmentally appropriate.

Conclusion

DSD include a wide range of diagnoses, some of which may require urogenital reconstruction to relieve obstruction, achieve continence, and/or address other anatomical differences whether cosmetic or functional. Adolescents and adults with DSD desired autonomy and to be part of the decision-making process. Parents were divided in their opinion of who should be involved in making elective surgical decisions: the child or parents as proxy medical decision-makers. Providers and other professionals stressed the importance of process and education around surgical decisions. Ongoing research examines how decision-makers evaluate tradeoffs associated with decision options.

Decisional Support Needed when Facing Tough Decisions: Survey of Parents with Children having Differences of Sex Development

Introduction

Parents of infants and young children newly diagnosed with differences of sex development (DSD) commonly face medical and psychosocial management decisions at a time when they are first learning about the condition and cannot consult their child for input. The aim of this study was to identify areas of greatest need for parental decisional support.

Methods

34 parents of children receiving care for DSD at one of three US children's hospitals participated in a survey to learn what clinical and psychosocial decisions needed to be made on behalf of their child. Parents were then asked to identify and focus on a "tough" decision and respond to questions assessing factors affecting decision-making, decision-making preferences, decisional conflict, and decision regret. Descriptive analyses were conducted.

Results

Decisions about surgery and aspects of sharing information about their child's condition with others were the two most frequently reported decisions overall, experienced by 97% and 88% of parents, as well as most frequently nominated as tough decisions. Many parents reported mild to moderate levels of decisional conflict (59%) and decision regret (74%). Almost all parents (94%) reported experiencing at least one factor as interfering with decision-making (e.g., "worried too much about choosing the 'wrong' option"). Parents universally reported a desire to be involved in decision-making - preferably making the final decision primarily on their own (79%), or together with their child's healthcare providers (21%). The majority of parents judged healthcare providers (82%) and patient/family organizations (58%) as trustworthy sources of information.

Discussion

Parents of children with DSD encounter medical, surgical, and psychosocial management decisions. Despite difficulties including emotional distress and informational concerns (including gaps and overload), parents express strong desires to play key roles in decision-making on behalf of their children. Healthcare providers can help identify family-specific needs through observation and inquiry in the clinical context. Together with families, providers should focus on specific clinical management decisions and support parental involvement in making decisions on behalf of young children with DSD.

Fertility in Individuals with Differences in Sex Development: Provider Knowledge Assessment

OBJECTIVE

Infertility is common among individuals with differences in sex development (DSD), and affected individuals and families desire fertility counseling. This survey sought to assess fertility knowledge and experiences with fertility counseling among DSD specialists for DSD conditions excluding congenital adrenal hyperplasia.

DESIGN, SETTING, PARTICIPANTS, AND MEASURES

A survey was iteratively developed by members of the DSD-Translational Research Network (DSD-TRN) Fertility Preservation Workgroup and disseminated to 5 clinician groups: the DSD-TRN, the Society for Pediatric Psychology DSD Special Interest Group (SIG), the Pediatric Endocrine Society DSD-SIG, the Societies for Pediatric Urology, and the North American Society for Pediatric and Adolescent Gynecology.

RESULTS

Completed surveys (n = 110) were mostly from pediatric urology (40.3%), gynecology (25.4%), and endocrinology (20.9%) specialists. Most (73/108, 67.6%) respondents reported discussing fertility potential. Sixty-seven responded to questions regarding fertility potential. Many participants answered questions about the presence of a uterus in individuals with 46,XY complete gonadal dysgenesis and about the potential for viable oocytes in individuals with 46,XY partial gonadal dysgenesis incorrectly. Comments acknowledged the need for further education on fertility in individuals with DSD.

CONCLUSIONS

Many DSD providers have some knowledge of fertility potential, but knowledge gaps remain. Experts expressed a desire for education and accessible resources to counsel effectively about fertility potential for individuals with DSD.

Pathological variants in genes associated with disorders of sex development and central causes of hypogonadism in a whole-genome reference panel of 8380 Japanese individuals

Disorders of sex development (DSD) comprises a congenital condition in which chromosomal, gonadal, or anatomical sex development is atypical. In this study, we screened for pathogenic variants in 32 genes associated with DSDs and central causes of hypogonadism (CHG) in a whole-genome reference panel including 8380 Japanese individuals constructed by Tohoku Medical Megabank Organization. Candidate pathogenic (P) or likely pathogenic (LP) variants were extracted from the ClinVar, InterVar, and Human Gene Mutation databases. Ninety-one candidate pathological variants were found in 25 genes; 28 novel candidate variants were identified. Nearly 1 in 40 (either ClinVar or InterVar P or LP) to 157 (both ClinVar and InterVar P or LP) individuals were found to be carriers of recessive DSD and CHG alleles. In these data, genes implicated in gonadal dysfunction did not show loss-of-function variants, with a relatively high tendency of intolerance for haploinsufficiency based on pLI and Episcore, both of which can be used for estimating haploinsufficiency. We report the types and frequencies of causative variants for DSD and CHG in the general Japanese population. This study furthers our understanding of the genetic causes and helps to refine genetic counseling of DSD and CHG.

Cohort profile: pathways to care among people with disorders of sex development (DSD)

PURPOSE

The 'DSD Pathways' study was initiated to assess health status and patterns of care among people enrolled in large integrated healthcare systems and diagnosed with conditions comprising the broad category of disorders (differences) of sex development (DSD). The objectives of this communication are to describe methods of cohort ascertainment for two specific DSD conditions-classic congenital adrenal hyperplasia with 46,XX karyotype (46,XX CAH) and complete androgen insensitivity syndrome (CAIS).

PARTICIPANTS

Using electronic health records we developed an algorithm that combined diagnostic codes, clinical notes, laboratory data and pharmacy records to assign each cohort candidate a 'strength-of-evidence' score supporting the diagnosis of interest. A sample of cohort candidates underwent a review of the full medical record to determine the score cutoffs for final cohort validation.

FINDINGS TO DATE

Among 5404 classic 46,XX CAH cohort candidates the strength-of-evidence scores ranged between 0 and 10. Based on sample validation, the eligibility cut-off for full review was set at the strength-of-evidence score of ≥7 among children under the age of 8 years and ≥8 among older cohort candidates. The final validation of all cohort candidates who met the cut-off criteria identified 115 persons with classic 46,XX CAH. The strength-of-evidence scores among 648 CAIS cohort candidates ranged from 2 to 10. There were no confirmed CAIS cases among cohort candidates with scores <6. The in-depth medical record review for candidates with scores ≥6 identified 61 confirmed cases of CAIS.

FUTURE PLANS

As the first cohort of this type, the DSD Pathways study is well-positioned to fill existing knowledge gaps related to management and outcomes in this heterogeneous population. Analyses will examine diagnostic and referral patterns, adherence to care recommendations and physical and mental health morbidities examined through comparisons of DSD and reference populations and analyses of health status across DSD categories.

Evolution of genes involved in the unusual genitals of the bear macaque, Macaca arctoides

Genital divergence is thought to contribute to reproductive barriers by establishing a “lock‐and‐key" mechanism for reproductive compatibility. One such example, Macaca arctoides, the bear macaque, has compensatory changes in both male and female genital morphology as compared to close relatives. M. arctoides also has a complex evolutionary history, having extensive introgression between the fascicularis and sinica macaque species groups. Here, phylogenetic relationships were analyzed via whole‐genome sequences from five species, including M. arctoides, and two species each from the putative parental species groups. This analysis revealed ~3x more genomic regions supported placement in the sinica species group as compared to the fascicularis species group. Additionally, introgression analysis of the M. arctoides genome revealed it is a mosaic of recent polymorphisms shared with both species groups. To examine the evolution of their unique genital morphology further, the prevalence of candidate genes involved in genital morphology was compared against genome‐wide outliers in various population genetic metrics of diversity, divergence, introgression, and selection, while accounting for background variation in recombination rate. This analysis identified 67 outlier genes, including several genes that influence baculum morphology in mice, which were of interest since the bear macaque has the longest primate baculum. The mean of four of the seven population genetic metrics was statistically different in the candidate genes as compared to the rest of the genome, suggesting that genes involved in genital morphology have increased divergence and decreased diversity beyond expectations. These results highlight specific genes that may have played a role in shaping the unique genital morphology in the bear macaque.

Utility of Chromosomal Microarray in Children with Unexplained Developmental Delay/Intellectual Disability

ObjectiveTo evaluate the chromosomal microarray (CMA) yield among children who presented with global developmental delay/intellectual disability (GDD/ID) with/without co-occurring conditions. Methods: The pathogenic copy number variation (pCNVs) findings on CMA of all children who presented with unexplained GDD/ID were categorized based on the clinical features. The karyotype results were compared with CMA. Results: The overall pCNV yield in children presenting with GDD/ID with or without comorbid conditions constituted 20.9%. Among the 17 pCNVs, 13 were losses and four were gains. Cardiac defect was the only co-morbidity in our study that demonstrated statistically significant prediction for pCNV (odds ratio 6.13, p value- 0.031). Six children who were karyotyped prior to CMA testing showed a structural abnormality. Conclusions: In our study, 20.9% of children with GDD/ID showed pCNVs on CMA. Cardiac defect alongside GDD/ID, emerged as the single strongest phenotype associated with pCNVs. CMA also provided vital information in previously karyotyped patients.

Primary Amenorrhea and Differences of Sex Development

Primary amenorrhea may be a feature or a presenting sign of a difference of sex development, most often due to a congenital anatomic difference or hypergonadotropic hypogonadism. History and physical exam are very important, including whether any variation in external genitalia was present at birth as well as a careful review of pubertal development. Further evaluation includes hormone measurement, imaging, and genetic evaluation. Those with a disorder of sexual development diagnosis should receive care through a multidisciplinary team with psychosocial support.

Disorders of Sex Development in a Large Ukrainian Cohort: Clinical Diversity and Genetic Findings

BACKGROUND

The clinical profile and genetics of individuals with Disorders/Differences of Sex Development (DSD) has not been reported in Ukraine.

MATERIALS AND METHODS

We established the Ukrainian DSD Register and identified 682 DSD patients. This cohort includes, 357 patients (52.3% [303 patients with Turner syndrome)] with sex chromosome DSD, 119 (17.5%) with 46,XY DSD and 206 (30.2%) with 46,XX DSD. Patients with sex chromosome DSD and congenital adrenal hyperplasia (CAH, n=185) were excluded from further studies. Fluorescence in situ hybridization (FISH) was performed for eight 46,XX boys. 79 patients underwent Whole Exome Sequencing (WES).

RESULTS

The majority of patients with 46,XY and 46,XX DSD (n=140), were raised as female (56.3% and 61.9% respectively). WES (n=79) identified pathogenic (P) or likely pathogenic (LP) variants in 43% of the cohort. P/LP variants were identified in the androgen receptor (AR) and NR5A1 genes (20.2%). Variants in other DSD genes including AMHR2, HSD17B3, MYRF, ANOS1, FGFR11, WT1, DHX37, SRD5A1, GATA4, TBCE, CACNA1A and GLI2 were identified in 22.8% of cases. 83.3% of all P/LP variants are novel. 35.3% of patients with a genetic diagnosis had an atypical clinical presentation. A known pathogenic variant in WDR11, which was reported to cause congenital hypogonadotropic hypogonadism (CHH), was identified in individuals with primary hypogonadism.

CONCLUSIONS

WES is a powerful tool to identify novel causal variants in patients with DSD, including a significant minority that have an atypical clinical presentation. Our data suggest that heterozygous variants in the WDR11 gene are unlikely to cause of CHH.

Genetics of human sexual development and related disorders

PURPOSE OF REVIEW

The aim of this study was to provide a basic overview on human sex development with a focus on involved genes and pathways, and also to discuss recent advances in the molecular diagnostic approaches applied to clinical workup of individuals with a difference/disorder of sex development (DSD).

RECENT FINDINGS

Rapid developments in genetic technologies and bioinformatics analyses have helped to identify novel genes and genomic pathways associated with sex development, and have improved diagnostic algorithms to integrate clinical, hormonal and genetic data. Recently, massive parallel sequencing approaches revealed that the phenotype of some DSDs might be only explained by oligogenic inheritance.

SUMMARY

Typical sex development relies on very complex biological events, which involve specific interactions of a large number of genes and pathways in a defined spatiotemporal sequence. Any perturbation in these genetic and hormonal processes may result in atypical sex development leading to a wide range of DSDs in humans. Despite the huge progress in the understanding of molecular mechanisms underlying DSDs in recent years, in less than 50% of DSD individuals, the genetic cause is currently solved at the molecular level.

Analysis of the androgen receptor (AR) gene in a cohort of Indonesian undermasculinized 46, XY DSD patients

Background

Pathogenic variants in the androgen receptor (AR) gene located on chromosome Xq11-12, are known to cause varying degrees of undermasculinization in 46, XY individuals. The aim of this study was to investigate the frequency of pathogenic variants in the AR gene in a cohort of 46, XY undermasculinized individuals from Indonesia who were suspected of having androgen insensitivity syndrome (AIS). All patients with 46, XY DSD referred to our center between 1994 and 2019 were collected from our clinical database. All 46, XY DSD patients without a prior molecular diagnosis with an external masculinization score (EMS) ≤ 9 were included in this study. All exons and intron–exon boundaries of AR gene were analyzed using Sanger sequencing to identify pathogenic variants of the AR gene.

Results

A cohort of 75 undermasculinized patients were selected for the study. Direct Sanger sequencing of all eight exons of the AR gene led to a genetic diagnosis in 11 patients (14.67%). All of the variants identified (p.Arg841His; p.Ile604Asn; p.Val731Met; p.Pro672Ser; p.Gln739Arg; p.Ser302Glufs*3) have been previously reported in patients with AIS.

Conclusions

This is the first study in Indonesia that highlights the significance of molecular analysis in providing a definitive diagnosis of AIS for patients with 46, XY DSD undermasculinization. This is an uncommon finding in the Indonesian population presenting with 46, XY DSD undermasculinization. A genetic diagnosis allows optimal clinical management and genetic counseling for patients and their families. As 46, XY DSD can be caused by pathogenic variants in other genes involved in gonadal development and differentiation, further genetic analysis, such as whole exome sequencing, should be carried out on those patients that did not carry an AR variant.

Molecular and Cytogenetic Analysis of Romanian Patients with Differences in Sex Development

Differences in sex development (DSD) are often correlated with a genetic etiology. This study aimed to assess the etiology of DSD patients following a protocol of genetic testing. Materials and methods. This study prospectively investigated a total of 267 patients with DSD who presented to Clinical Emergency Hospital for Children Cluj-Napoca between January 2012 and December 2019. Each patient was clinically, biochemically, and morphologically evaluated. As a first intervention, the genetic test included karyotype + SRY testing. A high value of 17-hydroxyprogesterone was found in 39 patients, in whom strip assay analysis of the CYP21A2 gene was subsequently performed. A total of 35 patients were evaluated by chromosomal microarray technique, and 22 patients were evaluated by the NGS of a gene panel. Results. The karyotype analysis established the diagnosis in 15% of the patients, most of whom presented with sex chromosome abnormalities. Genetic testing of CYP21A2 established a confirmation of the diagnosis in 44% of patients tested. SNP array analysis was particularly useful in patients with syndromic DSD; 20% of patients tested presented with pathogenic CNVs or uniparental disomy. Gene panel sequencing established the diagnosis in 11 of the 22 tested patients (50%), and the androgen receptor gene was most often involved in these patients. The genes that presented as pathogenic or likely pathogenic variants or variants of uncertain significance were RSPO1, FGFR1, WT1, CHD7, AR, NIPBL, AMHR2, AR, EMX2, CYP17A1, NR0B1, GNRHR, GATA4, and ATM genes. Conclusion. An evaluation following a genetic testing protocol that included karyotype and SRY gene testing, CYP21A2 analysis, chromosomal analysis by microarray, and high-throughput sequencing were useful in establishing the diagnosis, with a spectrum of diagnostic yield depending on the technique (between 15 and 50%). Additionally, new genetic variants not previously described in DSD were observed.

Oligogenic Causes of Human Differences of Sex Development: Facing the Challenge of Genetic Complexity

BACKGROUND

Deviations of intrauterine sex determination and differentiation and postnatal sex development can result in a very heterogeneous group of differences of sex development (DSD) with a broad spectrum of phenotypes. Variants in genes involved in sexual development cause different types of DSD, but predicting the phenotype from an individual's genotype and vice versa remains challenging.

SUMMARY

Next Generation Sequencing (NGS) studies suggested that oligogenic inheritance contributes to the broad manifestation of DSD phenotypes. This review will focus on possible oligogenic inheritance in DSD identified by NGS studies with a special emphasis on NR5A1variants as an example of oligogenic origin associated with a broad range of DSD phenotypes. We thoroughly searched the literature for evidence regarding oligogenic inheritance in DSD diagnosis with NGS technology and describe the challenges to interpret contribution of these genes to DSD phenotypic variability and pathogenicity. Key Messages: Variants in common DSD genes like androgen receptor (AR), mitogen-activated protein kinase kinase kinase 1 (MAP3K1), Hydroxy-Delta-5-Steroid Dehydrogenase 3 Beta- And Steroid Delta-Isomerase 2 (HSD3B2), GATA Binding Protein 4 (GATA4), zinc finger protein friend of GATA family member 2 (ZFPM2), 17b-hydroxysteroid dehydrogenase type 3 (HSD17B3), mastermind-like domain-containing protein 1 (MAMLD1), and nuclear receptor subfamily 5 group A member 1 (NR5A1) have been detected in combination with additional variants in related genes in DSD patients with a broad range of phenotypes, implying a role of oligogenic inheritance in DSD, while still awaiting proof. Use of NGS approach for genetic diagnosis of DSD patients can reveal more complex genetic traits supporting the concept of oligogenic cause of DSD. However, assessing the pathomechanistic contribution of multiple gene variants on a DSD phenotype remains an unsolved conundrum.

Towards improved genetic diagnosis of human differences of sex development

Despite being collectively among the most frequent congenital developmental conditions worldwide, differences of sex development (DSD) lack recognition and research funding. As a result, what constitutes optimal management remains uncertain. Identification of the individual conditions under the DSD umbrella is challenging and molecular genetic diagnosis is frequently not achieved, which has psychosocial and health-related repercussions for patients and their families. New genomic approaches have the potential to resolve this impasse through better detection of protein-coding variants and ascertainment of under-recognized aetiology, such as mosaic, structural, non-coding or epigenetic variants. Ultimately, it is hoped that better outcomes data, improved understanding of the molecular causes and greater public awareness will bring an end to the stigma often associated with DSD.

Differences of sex development in the newborn: from clinical scenario to molecular diagnosis

Differences/disorders of sex development (DSD) are defined as a group of congenital conditions in which the development of chromosomal, gonadal or anatomical sex is atypical. The incidence of DSD is 1:4500 births. The current classification divides DSDs into 3 categories according to chromosomal sex: 46,XX DSD, 46,XY DSD and sex chromosome DSD. DSD phenotypes can be concordant with the genotype (apparently normal external genitalia associated with gonadal dysgenesis), or can range from simply hypospadias to completely masculinised or feminised genitalia with a discordant karyotype. Numerous genes implicated in genital development have been reported. The search of genetic variants represents a central element of the extended investigation, as an improved knowledge of the genetic aetiology helps the immediate and long-term management of children with DSDs, in term of sex of rearing, hormone therapy, surgery, fertility and cancer risk. This review aims to assess the current role of molecular diagnosis in DSD management.

Reproductive health research in Australia and New Zealand: highlights from the Annual Meeting of the Society for Reproductive Biology, 2019

The 2019 meeting of the Society for Reproductive Biology (SRB) provided a platform for the dissemination of new knowledge and innovations to improve reproductive health in humans, enhance animal breeding efficiency and understand the effect of the environment on reproductive processes. The effects of environment and lifestyle on fertility and animal behaviour are emerging as the most important modern issues facing reproductive health. Here, we summarise key highlights from recent work on endocrine-disrupting chemicals and diet- and lifestyle-induced metabolic changes and how these factors affect reproduction. This is particularly important to discuss in the context of potential effects on the reproductive potential that may be imparted to future generations of humans and animals. In addition to key summaries of new work in the male and female reproductive tract and on the health of the placenta, for the first time the SRB meeting included a workshop on endometriosis. This was an important opportunity for researchers, healthcare professionals and patient advocates to unite and provide critical updates on efforts to reduce the effect of this chronic disease and to improve the welfare of the women it affects. These new findings and directions are captured in this review.

Survey of disorders of sex development in a large cohort of patients with diverse Mendelian phenotypes

Disorders of sex development (DSD) are congenital conditions with atypical development of chromosomal, gonadal, or anatomical sex. The estimated incidence ranges from 1 in 4,500-5,500 for strictly defined "ambiguous genitalia" to 1 in 300 or higher when a broader definition is implemented. In this study, we aim to define DSD phenotypes encountered in a large heterogeneous cohort of molecularly characterized Mendelian disorders in a single center. Data were retrieved for patients with documented abnormal genitalia based on the 2006 consensus criteria. Out of 149 patients (129 families) with compatible human phenotype ontology, 76 patients (68 families) had an identified genetic cause and were included in our analysis. Potentially causal variants were identified in 42 genes, and two patients had a dual molecular diagnosis. Six genes have no associated phenotype in OMIM (PIANP, CELSR2, USP2, FAM179B, TXNDC15, and CCDC96). Thirteen genes have non-DSD OMIM phenotypes, thus we are expanding their phenotype to include DSD. We also highlight how certain disorders are under-recognized despite their established DSD phenotype in OMIM, especially CTU2-related DREAM-PL syndrome and TSPYL1-related sudden infant death with dysgenesis of the testes syndrome. In conclusion, this study of a large heterogeneous Mendelian cohort expands the list of genes and disorders beyond those classically DSD-linked.

Applying Single-Cell Analysis to Gonadogenesis and DSDs (Disorders/Differences of Sex Development)

The gonads are unique among the body's organs in having a developmental choice: testis or ovary formation. Gonadal sex differentiation involves common progenitor cells that form either Sertoli and Leydig cells in the testis or granulosa and thecal cells in the ovary. Single-cell analysis is now shedding new light on how these cell lineages are specified and how they interact with the germline. Such studies are also providing new information on gonadal maturation, ageing and the somatic-germ cell niche. Furthermore, they have the potential to improve our understanding and diagnosis of Disorders/Differences of Sex Development (DSDs). DSDs occur when chromosomal, gonadal or anatomical sex are atypical. Despite major advances in recent years, most cases of DSD still cannot be explained at the molecular level. This presents a major pediatric concern. The emergence of single-cell genomics and transcriptomics now presents a novel avenue for DSD analysis, for both diagnosis and for understanding the molecular genetic etiology. Such -omics datasets have the potential to enhance our understanding of the cellular origins and pathogenesis of DSDs, as well as infertility and gonadal diseases such as cancer.

Newborn Screening Protocols and Positive Predictive Value for Congenital Adrenal Hyperplasia Vary across the United States

Newborn screening for congenital adrenal hyperplasia (CAH) caused by 21-hydroxylase deficiency is mandated throughout the US. Filter paper blood specimens are assayed for 17-hydroxyprogesterone (17OHP). Prematurity, low birth weight, or critical illness cause falsely elevated results. The purpose of this report is to highlight differences in protocols among US state laboratories. We circulated a survey to state laboratory directors requesting qualitative and quantitative information about individual screening programs. Qualitative and quantitative information provided by 17 state programs were available for analysis. Disease prevalence ranged from 1:9941 to 1:28,661 live births. Four state laboratories mandated a second screen regardless of the initial screening results; most others did so for infants in intensive care units. All but one program utilized birthweight cut-points, but cutoffs varied widely: 17OHP values of 25 to 75 ng/mL for birthweights >2250-2500 g. The positive predictive values for normal birthweight infants varied from 0.7% to 50%, with the highest predictive values based in two of the states with a mandatory second screen. Data were unavailable for negative predictive values. These data imply differences in sensitivity and specificity in CAH screening in the US. Standardization of newborn screening protocols could improve the positive predictive value.

Genetic disorders of sex development in cats: An update

Disorders of sex development (DSD) are rarely reported in cats, but this does not mean these occurrences are an insignificant reproductive and health problem in this species. The DSD condition affects reproduction and can be associated with an increased risk of gonadal tumorigenesis. In this review, an overview of findings since 2012 are presented that focus on cytogenetic and molecular genetic studies of cats with abnormal external genitalia. Results from advanced cytogenetic analysis of sex chromosomes indicate there is a range of abnormalities, including aneuploidies, structural rearrangements and freemartinism, which manifests as leukocyte XX/XY chimerism. The molecular abnormalities that result in feline monogenic and multifactorial DSD (such as hypospadias and cryptorchidism) are very few. There are only two mutations of genes (CYP11B1 and TAC3) which are known to be responsible for syndromes associated with abnormal sexual development. Several candidate genes (SRY, AR, SRD5A2, MAMLD1, DHH, HSD3B2, and HSD17B3) have also been examined, but no associations were identified between these polymorphisms and DSD phenotypes. The findings in developing the present review indicate sex chromosome abnormalities are quite common causes of feline DSD. The study of the molecular disorders that lead to the development of DSD in cats with normal XX or XY sex chromosome complements is still in its infancy, and further research is needed into this topic. It can be anticipated that the use of next generation sequencing technologies to study the genetic disorders that result in the DSD condition in cats will lead to an increase the detection of several causative mutations.

Loss-of-Function Variants in PPP1R12A: From Isolated Sex Reversal to Holoprosencephaly Spectrum and Urogenital Malformations

In two independent ongoing next-generation sequencing projects for individuals with holoprosencephaly and individuals with disorders of sex development, and through international research collaboration, we identified twelve individuals with de novo loss-of-function (LoF) variants in protein phosphatase 1, regulatory subunit 12a (PPP1R12A), an important developmental gene involved in cell migration, adhesion, and morphogenesis. This gene has not been previously reported in association with human disease, and it has intolerance to LoF as illustrated by a very low observed-to-expected ratio of LoF variants in gnomAD. Of the twelve individuals, midline brain malformations were found in five, urogenital anomalies in nine, and a combination of both phenotypes in two. Other congenital anomalies identified included omphalocele, jejunal, and ileal atresia with aberrant mesenteric blood supply, and syndactyly. Six individuals had stop gain variants, five had a deletion or duplication resulting in a frameshift, and one had a canonical splice acceptor site loss. Murine and human in situ hybridization and immunostaining revealed PPP1R12A expression in the prosencephalic neural folds and protein localization in the lower urinary tract at critical periods for forebrain division and urogenital development. Based on these clinical and molecular findings, we propose the association of PPP1R12A pathogenic variants with a congenital malformations syndrome affecting the embryogenesis of the brain and genitourinary systems and including disorders of sex development.

Next-Generation Sequencing Reveals Novel Genetic Variants (SRY, DMRT1, NR5A1, DHH, DHX37) in Adults With 46,XY DSD

CONTEXT

The genetic basis of human sex development is slowly being elucidated, and >40 different genetic causes of differences (or disorders) of sex development (DSDs) have now been reported. However, reaching a specific diagnosis using traditional approaches can be difficult, especially in adults where limited biochemical data may be available.

OBJECTIVE

We used a targeted next-generation sequencing approach to analyze known and candidate genes for DSDs in individuals with no specific molecular diagnosis.

PARTICIPANTS AND DESIGN

We studied 52 adult 46,XY women attending a single-center adult service, who were part of a larger cohort of 400 individuals. Classic conditions such as17β-hydroxysteroid dehydrogenase deficiency type 3, 5α-reductase deficiency type 2, and androgen insensitivity syndrome were excluded. The study cohort had broad working diagnoses of complete gonadal dysgenesis (CGD) (n = 27) and partially virilized 46,XY DSD (pvDSD) (n = 25), a group that included partial gonadal dysgenesis and those with a broad "partial androgen insensitivity syndrome" label. Targeted sequencing of 180 genes was undertaken.

RESULTS

Overall, a likely genetic cause was found in 16 of 52 (30.8%) individuals (22.2% CGD, 40.0% pvDSD). Pathogenic variants were found in sex-determining region Y (SRY; n = 3), doublesex and mab-3-related transcription factor 1 (DMRT1; n = 1), NR5A1/steroidogenic factor-1 (SF-1) (n = 1), and desert hedgehog (DHH; n = 1) in the CGD group, and in NR5A1 (n = 5), DHH (n = 1), and DEAH-box helicase 37 (DHX37; n = 4) in the pvDSD group.

CONCLUSIONS

Reaching a specific diagnosis can have clinical implications and provides insight into the role of these proteins in sex development. Next-generation sequencing approaches are invaluable, especially in adult populations or where diagnostic biochemistry is not possible.

Disorders of sex development: Genetic characterization of a patient cohort

Disorders of sex development (DSDs) are congenital conditions in which the external appearance of the individual does not coincide with the chromosomal constitution or the gonadal sex. In other words, there is an ambiguous or intermediate condition between the male and female phenotypes of the anatomical sex. These atypical conditions are manifested in several ways, ranging from genital ambiguity to phenotypes that are so attenuated that they can go unnoticed or appear normal. Currently, there is a lack of understanding of the factors responsible for these outcomes; however, they are likely to be conditioned by genetic, hormonal and environmental factors during prenatal and postnatal development. The present study determined the genetic etiology of DSDs in Colombian patients by conventional cytogenetic analysis, FISH and MLPA (for SF1, DAX1, SOX9, SRY and WNT4). A cohort of 43 patients with clinical phenotypes of sex development disorder was used in the present study. Using this multistep experimental approach, a diagnostic percentage of 25.58% was obtained: 17 patients (39.53%) were classified as having gonadal development disorders, the majority of which were ovotesticular disorders with numerical and/or structural alterations of the sex chromosomes, 9 patients (20.93%) were classified as having testicular DSD with a 46,XY karyotype, and 3 patients (6.98%) as having ovarian DSD with a 46,XX karyotype. The remaining 14 patients (32.56%) were classified as 'other' since they could not be grouped into a specific class of gonadal development, corresponding to hypospadias and multiple congenital anomalies. These findings highlight the importance of histological and cytogenetic studies in a gonadal biopsy. In 11/43 cases, the multistep experimental protocol presented in the present study yielded etiological or histological findings that could be used to define the medical management of patients with DSDs. In conclusion, for the etiological diagnosis of DSDs, a broad‑spectrum approach that includes endocrinological tests, conventional karyotyping, molecular karyotyping by FISH and, molecular tests is required, in addition to gonadal tissue analyses, to identify genetic alterations.

A clinical algorithm to diagnose differences of sex development

The diagnosis and management of children born with ambiguous genitalia is challenging for clinicians. Such differences of sex development (DSDs) are congenital conditions in which chromosomal, gonadal, or anatomical sex is atypical. The aetiology of DSDs is very heterogenous and a precise diagnosis is essential for management of genetic, endocrine, surgical, reproductive, and psychosocial issues. In this Review, we outline a step-by-step approach, compiled in a diagnostic algorithm, for the clinical assessment and molecular diagnosis of a patient with ambiguity of the external genitalia on initial presentation. We appraise established and emerging technologies and their effect on diagnosis, and discuss current controversies.

Disorders of sex development (DSD) web-based information: quality survey of DSD team websites

Objectives

Consumers rely on online health information, particularly for unusual conditions. Disorders of Sex Development (DSD) are complex with some aspects of care controversial. Accurate web-based DSD information is essential for decision-making, but the quality has not been rigorously evaluated. The purpose of the present study was to assess the quality of online health information related to DSD presented by 12 pediatric institutions comprising the NIH-sponsored DSD-Translational Research Network (DSD-TRN).

Methods

DSD-TRN sites identified team webpages, then we identified linked webpages. We also used each institution search engine to search common DSD terms. We assessed webpages using validated tools: the Simple Measure of Gobbledygook (SMOG) determined reading level, the Patient Education Materials Assessment Tool (PEMAT) evaluated content for understandability and actionability, and the DISCERN tool assessed treatment decision-making information (for hormone replacement and surgery). We developed a “Completeness” measure which assessed the presence of information on 25 DSD topics.

Results

The SMOG reading level of webpages was at or above high-school grade level. Mean (SD) PEMAT understandability score for Team Pages and Team Links was 68% (6%); on average these pages met less than 70% of the understandability criteria. Mean (SD) PEMAT actionability score was 23% (20%); few patient actions were identified. The DISCERN tool determined that the quality of information related to hormone treatment and to surgery was poor. Sites’ webpages covered 12–56% of the items on our Completeness measure.

Conclusions

Quality of DSD online content was poor, and would be improved by using a variety of strategies, such as simplifying word choice, using visual aids, highlighting actions patients can take and acknowledging areas of uncertainty. For complex conditions such as DSD, high-quality web-based information is essential to empower patients (and caregiver proxies), particularly when aspects of care are controversial.

Translating genomics to the clinical diagnosis of disorders/differences of sex development

The medical and psychosocial challenges faced by patients living with Disorders/Differences of Sex Development (DSD) and their families can be alleviated by a rapid and accurate diagnostic process. Clinical diagnosis of DSD is limited by a lack of standardization of anatomical and endocrine phenotyping and genetic testing, as well as poor genotype/phenotype correlation. Historically, DSD genes have been identified through positional cloning of disease-associated variants segregating in families and validation of candidates in animal and in vitro modeling of variant pathogenicity. Owing to the complexity of conditions grouped under DSD, genome-wide scanning methods are better suited for identifying disease causing gene variant(s) and providing a clinical diagnosis. Here, we review a number of established genomic tools (karyotyping, chromosomal microarrays and exome sequencing) used in clinic for DSD diagnosis, as well as emerging genomic technologies such as whole-genome (short-read) sequencing, long-read sequencing, and optical mapping used for novel DSD gene discovery. These, together with gene expression and epigenetic studies can potentiate the clinical diagnosis of DSD diagnostic rates and enhance the outcomes for patients and families.

Baseline Characteristics of Infants With Atypical Genital Development: Phenotypes, Diagnoses, and Sex of Rearing

Purpose

Little is known about the phenotypes, diagnoses, and sex of rearing of infants with atypical genital development in the United States. As part of a multicenter study of these infants, we have provided a baseline report from US difference/disorder of sex development clinics describing the diagnoses, anatomic features, and sex of rearing. We also determined whether consensus guidelines are followed for sex designation in the United States.

Methods

Eligible participants had moderate-to-severe genital atypia, were aged <3 years, and had not undergone previous genitoplasty. Karyotype, genetic diagnosis, difference/disorder of sex development etiology, family history, and sex of rearing were collected. Standardized examinations were performed.

Results

Of 92 subjects, the karyotypes were 46,XX for 57%, 46,XY for 34%, and sex chromosome abnormality for 9%. The median age at the baseline evaluation was 8.8 months. Most 46,XX subjects (91%) had congenital adrenal hyperplasia (CAH) and most 46,XY subjects (65%) did not have a known diagnosis. Two individuals with CAH underwent a change in sex of rearing from male to female within 2 weeks of birth. The presence of a uterus and shorter phallic length were associated with female sex of rearing. The most common karyotype and diagnosis was 46,XX with CAH, followed by 46,XY with an unknown diagnosis. Phenotypically, atypical genitalia have been most commonly characterized by abnormal labioscrotal tissue, phallic length, and urethral meatus location.

Conclusions

An increased phallic length was positively associated with rearing male. Among the US centers studied, sex designation followed the Consensus Statement recommendations. Further study is needed to determine whether this results in patient satisfaction.

The Role of Patient Advocacy and the Declining Rate of Clitoroplasty in 46,XX Patients With Congenital Adrenal Hyperplasia

Prior to the 1990s, most 46,XX infants with clitoromegaly secondary to congenital adrenal hyperplasia were treated with feminizing genitoplasty to make their cosmetic appearance congruent with their genotypic sex. A 2006 consensus statement for the management of intersex disorders accepted input from patient advocates and did not support purely cosmetic surgery for clitoromegaly. This study examined the extent to which the desired change was implemented in practice. Retrospective chart review was performed at a single Midwestern tertiary care medical center for patients born between 1979 and 2013. Of 45 virilized patients, 40 had clitoromegaly and 39 had urogenital sinus or posterior labial fusion. Twenty-seven (67.5%) patients underwent clitoroplasty and 33 (84.6%) underwent perineoplasty, including vaginoplasty, urethroplasty, imperforate vagina repair, and/or posterior labial fusion repair. There was a linear decline in the rate of clitoroplasty over time for the patient cohort. This study demonstrates the power of patient advocacy to improve medical practice.

Navigating Surgical Decision Making in Disorders of Sex Development (DSD)

Surgical management of disorders of sex development (DSD) is associated with contentious debate between and within stakeholder communities. While the intent of surgical management of the genitals and gonads is to benefit the patient physically and psychosocially, these goals have not always been achieved; reports of harm have surfaced. Harm experienced by some patients has resulted in the emergence of an activist platform calling for a moratorium on all surgical procedures during childhood-excepting those forestalling threats to life within the childhood years. This ban is not universally endorsed by patient advocacy groups. Parents, meanwhile, continue to need to make decisions regarding surgical options for their young children. Constructive paths forward include implementation of Consensus Statement recommendations that call for comprehensive and integrated team care, incorporating mental health services, and adopting shared decision making.

New technologies to uncover the molecular basis of disorders of sex development

The elegant developmental biology experiments conducted in the 1940s by French physiologist Alfred Jost demonstrated that the sexual phenotype of a mammalian embryo depended whether the embryonic gonad develops into a testis or not. In humans, anomalies in the processes that regulate development of chromosomal, gonadal or anatomic sex result in a spectrum of conditions termed Disorders/Differences of Sex Development (DSD). Each of these conditions is rare, and understanding of their genetic etiology is still incomplete. Historically, DSD diagnoses have been difficult to establish due to the lack of standardization of anatomical and endocrine phenotyping procedures as well as genetic testing. Yet, a definitive diagnosis is critical for optimal management of the medical and psychosocial challenges associated with DSD conditions. The advent in the clinical realm of next-generation sequencing methods, with constantly decreasing price and turnaround time, has revolutionized the diagnostic process. Here we review the successes and limitations of the genetic methods currently available for DSD diagnosis, including Sanger sequencing, karyotyping, exome sequencing and chromosomal microarrays. While exome sequencing provides higher diagnostic rates, many patients still remain undiagnosed. Newer approaches, such as whole-genome sequencing and whole-genome mapping, along with gene expression studies, have the potential to identify novel DSD-causing genes and significantly increase total diagnostic yield, hopefully shortening the patient's journey to an accurate diagnosis and enhancing health-related quality-of-life outcomes for patients and families.

Identification of novel candidate genes for 46,XY disorders of sex development (DSD) using a C57BL/6J-Y POS mouse model

BACKGROUND

Disorders of sex development (DSD) have an estimated frequency of 0.5% of live births encompassing a variety of urogenital anomalies ranging from mild hypospadias to a discrepancy between sex chromosomes and external genitalia. In order to identify the underlying genetic etiology, we had performed exome sequencing in a subset of DSD cases with 46,XY karyotype and were able to identify the causative genetic variant in 35% of cases. While the genetic etiology was not ascertained in more than half of the cases, a large number of variants of unknown clinical significance (VUS) were identified in those exomes.

METHODS

To investigate the relevance of these VUS in regards to the patient's phenotype, we utilized a mouse model in which the presence of a Y chromosome from the poschiavinus strain (Y POS ) on a C57BL/6J (B6) background results in XY undervirilization and sex reversal, a phenotype characteristic to a large subset of human 46,XY DSD cases. We assessed gene expression differences between B6-Y B6 and undervirilized B6-Y POS gonads at E11.5 and identified 515 differentially expressed genes (308 underexpressed and 207 overexpressed in B6-Y POS males).

RESULTS

We identified 15 novel candidate genes potentially involved in 46,XY DSD pathogenesis by filtering the list of human VUS-carrying genes provided by exome sequencing with the list of differentially expressed genes from B6-Y POS mouse model. Additionally, we identified that 7 of the 15 candidate genes were significantly underexpressed in the XY gonads of mice with suppressed Sox9 expression in Sertoli cells suggesting that some of the candidate genes may be downstream of a well-known sex determining gene, Sox9.

CONCLUSION

The use of a DSD-specific animal model improves variant interpretation by correlating human sequence variants with transcriptome variation.

Psychosocial Screening in Disorders/Differences of Sex Development: Psychometric Evaluation of the Psychosocial Assessment Tool

BACKGROUND/AIMS

Utilization of a psychosocial screener to identify families affected by a disorder/difference of sex development (DSD) and at risk for adjustment challenges may facilitate efficient use of team resources to optimize care. The Psychosocial Assessment Tool (PAT) has been used in other pediatric conditions. The current study explored the reliability and validity of the PAT (modified for use within the DSD population; PAT-DSD).

METHODS

Participants were 197 families enrolled in the DSD-Translational Research Network (DSD-TRN) who completed a PAT-DSD during a DSD clinic visit. Psychosocial data were extracted from the DSD-TRN clinical registry. Internal reliability of the PAT-DSD was tested using the Kuder-Richardson-20 coefficient. Validity was examined by exploring the correlation of the PAT-DSD with other measures of caregiver distress and child emotional-behavioral functioning.

RESULTS

One-third of families demonstrated psychosocial risk (27.9% "Targeted" and 6.1% "Clinical" level of risk). Internal reliability of the PAT-DSD Total score was high (α = 0.86); 4 of 8 subscales met acceptable internal reliability. A priori predicted relationships between the PAT-DSD and other psychosocial measures were supported. The PAT-DSD Total score related to measures of caregiver distress (r = 0.40, p < 0.001) and to both caregiver-reported and patient self-reported behavioral problems (r = 0.61, p < 0.00; r = 0.37, p < 0.05).

CONCLUSIONS

This study provides evidence for the reliability and validity of the PAT-DSD. Given variability in the internal reliability across subscales, this measure is best used to screen for overall family risk, rather than to assess specific psychosocial concerns.

Emerging issues in disorders/differences of sex development (DSD)

Disorders/Differences of Sex Development (DSD), as defined by the 2006 Consensus Statement, are "congenital conditions in which development of chromosomal, gonadal, or anatomic sex is atypical." They represent a spectrum of chronic medical conditions collectively affecting about 1% of the population and are associated with increased risk of infertility, cancer, and psychosocial distress. Clinical management in DSD is subject to multiple controversies about gender assignment, the timing and appropriateness of genital surgery and the approach to disclosure. There is dissent within and between stakeholders (healthcare providers, advocacy groups, families) regarding what constitutes optimal care. This special issue investigates the progress made as well as the uncertainties remaining a decade after the consensus statement and the gaps to be filled by future research and improved clinical practice. It discusses the increasing intricacy of genetic variant interpretation in the era of next-generation sequencing and the associated complexity of phenotypic variability. The issue tackles ethical dilemmas and the complicated decision-making process of assignment of sex of rearing at birth in cases of 5-alpha reductase type 2 deficiency, surveys delivery of clinical services in the United States, discusses challenges of interdisciplinary care and of educating patients and parents about DSD,and reviews the factors predisposing to gonadal tumor and their consequences on clinical management.