The clinical and genetic heterogeneity of mixed gonadal dysgenesis: does "disorders of sexual development (DSD)" classification based on new Chicago consensus cover all sex chromosome DSD?

Genetic control of typical and atypical sex development

Sex development relies on the sex-specific action of gene networks to differentiate the bipotential gonads of the growing fetus into testis or ovaries, followed by the differentiation of internal and external genitalia depending on the presence or absence of hormones. Differences in sex development (DSD) arise from congenital alterations during any of these processes, and are classified depending on sex chromosomal constitution as sex chromosome DSD, 46,XY DSD or 46,XX DSD. Understanding the genetics and embryology of typical and atypical sex development is essential for diagnosing, treating and managing DSD. Advances have been made in understanding the genetic causes of DSD over the past 10 years, especially for 46,XY DSD. Additional information is required to better understand ovarian and female development and to identify further genetic causes of 46,XX DSD, besides congenital adrenal hyperplasia. Ongoing research is focused on the discovery of further genes related to typical and atypical sex development and, therefore, on improving diagnosis of DSD.

Surgery in Chinese children affected by 45,X/46,XY disorders of sex development: A 20-year experience in a single center

BACKGROUND

Children affected by 45,X/46,XY mosaicism have a wide spectrum in their phenotypes. Although surgery has a role in management, there is no universally agreed strategy.

METHODS

We conducted a retrospective review in a tertiary center on the surgical management and its long-term outcomes in children with the karyotype 45,X/46,XY or its variants over a 20-year study period. Patients were divided into 4 groups based on their phenotypes.

RESULTS

22 children(female=13, male=9) were included in the study, and were grouped as I)female phenotype(n = 11), II)ambiguous external genitalia(n = 2), III)undervirilized male with hypospadias(n = 6), and IV)normal male phenotype(n = 3). 19/22(86%) underwent gonadal surgeries(bilateral gonadectomy=15; unilateral gonadectomy=1; testicular biopsy=3) and  8/22(36%) underwent genitalia reconstructive surgeries(hypospadias repair=6; feminizing surgery=2). Gonadal germ cell tumors were detected in 55%, 50% and 50% of Group I, II and III respectively. 3/6 patients required reoperations for complications after hypospadias repairs. None of the patients had recurrence of germ cell tumors after gonadectomy. All the patients who had reached late adolescence or adulthood maintained their genders as their sex of rearing.

CONCLUSIONS

Majority of 45,X/46,XY children benefit from timely gonadal surgery while genitalia reconstructive surgery can be considered in selected patients. Surgical management can be strategized by patients' phenotypes.

Sex attribution, gender identity and quality of life in disorders of sex development due to 45,X/46,XY mosaicism: methods for clinical and psychosocial assessment

The choice of sex in newborns with genital ambiguity is challenging. Information concerning the satisfaction of subjects with disorders of sex development from childhood to adulthood is required in order to address sex attribution policies. This study focuses on the methods that enable clinicians to investigate the alignment of phenotypes with gender identity and quality of life in people with disorders of this kind. These methods are presented as tools for studying a cohort of ten subjects with 45,X/46,XY mosaicism examined between 1985 and 2014 in the Department of Pediatric Endocrinology, Regina Margherita Children's Hospital, Turin: five children and five young adults, four reared as females and six as males. Clinical outcome was assessed by means of a clinical scoring system considering height, genital appearance, gonads and pubertal development. The Gender Identity Questionnaire for Children and the World Health Organization Quality of Life assessment were adopted. The four male children strongly identified with their assigned sex: male attribution was satisfactory until pubertal age. In young adults the clinical scores ranged between 55–65% for both genders. In the young male, the reduced sexual activity and the poor body image perception strongly affected his quality of life. The clinical scores of the two young female adults (60% for both) were not balanced with their quality of life scores (87.5% and 68.75% respectively): individual traits and social-familial context should be investigated in order to explain these differences. Clinical and psychosocial assessment in people with disorders of sex development is mandatory in order to plan care procedures; a detailed analysis requires adequate tools. Clinical scoring system, Gender Identity Questionnaire for Children and World Health Organization Quality of Life assessment can be used to investigate the alignment of physical phenotype with gender identity and quality of life.

A novel SRD5A2 mutation in an Iranian family with sex development disorder

Disorders of sex development (DSD) are different types of conditions that their accurate diagnosis by using conventional phenotypic and biochemical approaches is a challenging issue. Precise determination of DSD is critical due to the detection of possible life-threatening associated disorders. It may also assist parents in choosing the most suitable management for their affected child. In this study, two affected kids born from consanguineous families who were clinically diagnosed for sex development disorder were investigated for the main cause of the disease. Biochemical analysis failed to make an accurate diagnosis. Karyotype analysis showed an abnormal sex chromosome pattern. Whole exome sequencing was sequentially applied to precisely ascertain the genetic cause of the disease. A novel deletion, g.40936_53878del12943insTG (NG_008365.1), and one known mutation, c.586G>A (p.Gly196Ser), were detected in SRD5A2 gene in case I and case II respectively. Further analysis was performed using polymerase chain reaction, primer walking and Sanger sequencing to detect the nucleotides changes accurately. Segregation analysis in the families confirmed 13kb novel homozygous deletion of SRD5A2 in case I and c.586G>A in case II. The present study confirms the diagnostic value of whole exome sequencing in the detection of DSD aetiology, especially when several differential diagnoses are possible.

Pubertal outcomes and sex of rearing of patients with ovotesticular disorder of sex development and mixed gonadal dysgenesis

PURPOSE

Patients with ovotesticular disorder of sex development (DSD) and mixed gonadal dysgenesis (MGD) usually present with asymmetric gonads and have wide phenotypic variations in internal and external genitalia. The differential diagnosis of these conditions is based on karyotype and pathological findings of the gonads. This study investigated the clinical features at presentation, karyotype, sex of rearing, and pubertal outcomes of patients with ovotesticular DSD and MGD.

METHODS

The study comprised 23 patients with DSD who presented with asymmetric gonads. The presenting features, karyotype, sex of rearing, and pubertal outcomes were reviewed retrospectively.

RESULTS

All 23 patients presented with ambiguous genitalia at a median age of 1 month (range, 1 day-1.6 years). Müllerian duct remnants were identified in 15 of 23 patients (65.2%). Fourteen patients were diagnosed with ovotesticular DSD, whereas the other 9 were diagnosed with MGD. Eight of 14 patients (57.1%) with ovotesticular DSD were raised as males, while 7 of 9 patients with MGD (77.8%) were assigned as males. One male-assigned patient with ovotesticular DSD changed to female sex at age 20 years.

CONCLUSION

Patients with ovotesticular DSD and MGD manifest overlapping clinical presentations and hormonal profiles. It is difficult to determine the sex of rearing and predict long-term pubertal outcomes. Therefore, long-term follow-up is required to monitor spontaneous puberty, sex outcome, and urological and gynecological complications.

Clinical but Not Histological Outcomes in Males With 45,X/46,XY Mosaicism Vary Depending on Reason for Diagnosis

CONTEXT

Larger studies on outcomes in males with 45,X/46,XY mosaicism are rare.

OBJECTIVE

To compare health outcomes in males with 45,X/46,XY diagnosed as a result of either genital abnormalities at birth or nongenital reasons later in life.

DESIGN

A retrospective, multicenter study.

SETTING

Sixteen tertiary centers.

PATIENTS OR OTHER PARTICIPANTS

Sixty-three males older than 13 years with 45,X/46,XY mosaicism.

MAIN OUTCOME MEASURES

Health outcomes, such as genital phenotype, gonadal function, growth, comorbidities, fertility, and gonadal histology, including risk of neoplasia.

RESULTS

Thirty-five patients were in the genital group and 28 in the nongenital. Eighty percent of all patients experienced spontaneous pubertal onset, significantly more in the nongenital group (P = 0.023). Patients were significantly shorter in the genital group with median adult heights of 156.7 cm and 164.5 cm, respectively (P = 0.016). Twenty-seven percent of patients received recombinant human GH. Forty-four patients had gonadal histology evaluated. Germ cells were detected in 42%. Neoplasia in situ was found in five patients. Twenty-five percent had focal spermatogenesis, and another 25.0% had arrested spermatogenesis. Fourteen out of 17 (82%) with semen analyses were azoospermic; three had motile sperm.

CONCLUSION

Patients diagnosed as a result of genital abnormalities have poorer health outcomes than those diagnosed as a result of nongenital reasons. Most patients, however, have relatively good endocrine gonadal function, but most are also short statured. Patients have a risk of gonadal neoplasia, and most are azoospermic, but almost one-half of patients has germ cells present histologically and up to one-quarter has focal spermatogenesis, providing hope for fertility treatment options.

Frequency of Ambiguous Genitalia in 14,177 Newborns in Turkey

CONTEXT

Limited data are available on the exact incidence of disorders of sex development (DSD) with genital ambiguity at birth.

OBJECTIVE

To determine frequency of ambiguous genitalia in newborns.

DESIGN

Prospective multicenter study.

SETTING

Three tertiary care hospitals.

PATIENTS OR OTHER PARTICIPANTS

All 14,177 babies born during the study period were included.

MAIN OUTCOME MEASURES

All newborns were examined at birth; data on weeks of gestation, birth weight, and length were collected. A structured questionnaire was used for data collection. Quigley and Prader scales were used for phenotypic grading. Clinical and genetic investigations were performed.

RESULTS

Eighteen babies with ambiguous genitalia were found among 14,177 newborns (1.3/1000). Fifteen newborns had 46,XY DSD, one had 46,XX congenital adrenal hyperplasia, and one had 45,X/46,XY mixed gonadal dysgenesis. Karyotype analysis was not done in one baby who died in the neonatal period. The ratio of prematurity was higher in the DSD group (44% vs 11%; P < 0.001) and the ratio of small for gestational age was also higher in the DSD group (22% vs 5%; P = 0.007). Eight babies with DSD had mothers who had additional medical conditions, such as preeclampsia, depression, insulin resistance, and gestational diabetes mellitus.

CONCLUSION

The frequency of ambiguous genitalia was higher than in previous studies, but, as with any experiment, the finding should be met with caution because this study was conducted in tertiary care hospitals. In addition, lower birth weight in the DSD group supports the hypothesis that early placental dysfunction might be important in the etiology of male genital anomalies.

Growth data and tumour risk of 32 Chinese children and adolescents with 45,X/46,XY mosaicism

BACKGROUND

The aim of this study was to review the growth data, gonadal function and tumour risk of children and adolescents with 45,X/46,XY mosaicism who presented to a single centre in China.

METHODS

We conducted a retrospective review of the records of 32 patients with 45,X/46,XY mosaicism or variants who were hospitalized from August 2005 to September 2018. The main outcomes measured were growth data, genital phenotype, gonadal function, gonadal position, and histological results.

RESULTS

A total of 32 patients were included. The age at diagnosis ranged from 0.6 to 16.3 years. Nineteen patients exhibited ambiguous genitalia, 12 had short stature, and 1 showed a lack of breast development. Seventeen patients were raised as males, and 15 were raised as females. The external masculinisation score (EMS) of patients raised as male was 4.5 (1~12) [median (range)]. The EMS of the females was 0 (0~1.5) [median (range)]. Patients showed normal heights under 2 years old, with a height SDS of 0 (- 1.5~1.4) [median (range)]. Growth appeared to decelerate after age 2 years, with SDS decreased to - 2.8 (- 3.0~ - 0.9) [median (range)]. The percentage of short stature was higher in females than in males (76.9% vs 50.0%). Twenty-five patients had gonadal pathological results. Complete gonadal dysgenesis (CGD) and mixed gonadal dysgenesis (MGD) were the most common pathogenic subtypes, accounting for 48.0 and 36.0%, respectively. Ovotesticular tissue was observed in only 4.0% of patients. Gonadoblastoma and positive OCT3/4 results were found in 18.8% of gonads in children over 2 years of age. Palpable gonads accounted for 50% of these. All patients who had gonadoblastoma were raised as females.

CONCLUSIONS

Patients with 45,X/46,XY might have normal heights until 2 years old. Growth decelerations after 2 years of age were common. Patients who are being raised as females seemed to be shorter than males. CGD and MGD were the most common gonadal pathogenic subtypes. The tumour risk is high in these patients, even in palpable gonads and female patients.

Management of pediatric patients with DSD and ambiguous genitalia: Balancing the child's moral claims to self-determination with parental values and preferences

INTRODUCTION

A central ethical dilemma in management of the patient with a disorder of sex development (DSD) is the potential conflict between respect for the fundamental right of the child for physical and emotional integrity and self-determination, and the right of parents to serve as surrogate decision-makers and act in their child's best interest.

METHODS

Over the past 2 years we have encountered three complex DSD cases on the spectrum of mixed gonadal dysgenesis to ovotesticular DSD in which gender assignment and therefore optimal surgical management was uncertain. All patients had mosaic karyotypes with Y chromosome, dysgenetic ovary and dysgenetic testis, a urogenital sinus, and prominent phallus. In all three cases a team approach was taken to assess functional potential and risks along either gender pathway and to develop a spectrum of treatment options for parental consideration, including: 1. masculinization with removal of dysgenetic ovary; 2. initial vaginoplasty but with retention of the phallus (±bilateral gonadectomy); 3. initial vaginoplasty with "burial" of corporal bodies (Pippi Salle procedure) (±bilateral gonadectomy); 4. full feminization: vaginoplasty and clitoroplasty (with bilateral gonadectomy); 5. no surgical intervention.

RESULTS

In all three cases, after consideration of risks and benefits of all options, parents selected option 2: gonadectomy to eliminate tumor risk and vaginoplasty, taking advantage of the child's young age to exteriorize urinary and reproductive tracts to avoid incontinence and infection and supporting parental bias toward female gender, but preservation of phallic structures to ensure a male option should the patient later declare a male gender identity. Parents of the three patients were contacted post-operatively (at 7, 17, and 22 months) for follow-up. All (3/3) regarded their child's development and wellbeing positively, and their own decisions regarding gender assignment and surgical plan favorably. All (3/3) regarded the team advisory process as balanced and supportive.

CONCLUSION

In the setting of exposure of the neonatal brain to testosterone, vaginoplasty and phallic preservation afforded a balance between parental preferences and preservation of anatomic options, allowing potential reconstruction of male or female phenotype as gender identity is ascertained thereby respecting both parent and patient rights. Parents valued a spectrum of options, transparency, and the team decision-making process.

Klinefelter Syndrome in Childhood: Variability in Clinical and Molecular Findings

OBJECTIVE

Klinefelter syndrome (KS) is the most common (1/500–1/1000) chromosomal disorder in males, but only 10% of cases are identified in childhood. This study aimed to review the data of children with KS to assess the age and presenting symptoms for diagnosis, clinical and laboratory findings, together with the presence of comorbidities.

METHODS

Twenty-three KS patients were analyzed retrospectively. Age at admission, presenting symptoms, comorbid problems, height, weight, pubertal status, biochemical findings, hormone profiles, bone mineral density and karyotype were evaluated. Molecular analysis was also conducted in patients with ambiguous genitalia.

RESULTS

The median age of patients at presentation was 3.0 (0.04-16.3) years. Most of the cases were diagnosed prenatally (n=15, 65.2%). Other reasons for admission were scrotal hypospadias (n=3, 14.3%), undescended testis (n=2, 9.5%), short stature (n=1, 4.8%), isolated micropenis (n=1, 4.8%) and a speech disorder (n=1, 4.8%). The most frequent clinical findings were neurocognitive disorders, speech impairment, social and behavioral problems and undescended testes. All except two patients were prepubertal at admission. Most of the patients (n=20, 86.9%) showed the classic 47,XXY karyotype. Steroid 5 alpha-reductase 2 gene and androgen receptor gene mutations were detected in two of the three cases with genital ambiguity.

CONCLUSION

Given the large number of underdiagnosed KS patients before adolescence, pediatricians need to be aware of the phenotypic variability of KS in childhood. Genetic analysis in KS patients may reveal mutations associated with other forms of disorders of sex development besides KS.

Clinical heterogeneity in children with gonadal dysgenesis associated with non-mosaic 46,XY karyotype

INTRODUCTION

Gonadal dysgenesis is unique in disorders of sex development (DSD), in that it can be associated with 46,XX, 46,XY or mosaic 45,X/46,XY karyotypes. Gonadal dysgenesis can be partial or complete. Gonadal dysgenesis associated with the Y-chromosome has increased risk of gonadal germ cell neoplasms. Most of the literature focus on 45,X/46,XY gonadal dysgenesis, while there are scanty data on the condition when the karyotype is non-mosaic 46,XY.

OBJECTIVE

To investigate the diversity of clinical pictures of children presenting with 46,XY DSD due to gonadal dysgenesis.

METHODS

A retrospective study on consecutive patients diagnosed with 46,XY gonadal dysgenesis at age ≤18 years in a tertiary center from 1985 to 2015. The clinical presentations, phenotypes, gonadal features and associated anomalies were investigated.

RESULTS

Twenty-eight patients with Y-chromosome gonadal dysgenesis were identified during the study period and six (21.4%) had non-mosaic 46,XY karyotype. Three had complete gonadal dysgenesis (CGD) with normal female phenotype, while the other three had partial gonadal dysgenesis (PGD). Of the three patients with CGD, two presented with the classical Swyer syndrome at adolescence, while the third presented at birth with multiple congenital anomalies. The three PGD patients presented with ambiguous genitalia at birth (n = 2), and isolated hypospadias (n = 1), which was associated with Frasier syndrome. Three patients had germ cell neoplasms: bilateral gonadoblastoma (n = 1), bilateral intratubular germ cell neoplasia unclassified (n = 1), and dysgerminoma + gonadoblastoma (n = 1). Two patients had global developmental delay with other congenital anomalies, and another patient had learning difficulties with borderline intelligence (Table).

DISCUSSION

The findings suggest that 46,XY gonadal dysgenesis is much rarer than 45,X/46,XY gonadal dysgenesis. Patients differed in their clinical presentations and well-established syndromes happened in half of them. Overall, the risk of germ cell neoplasms and the association with other somatic anomalies appeared to be high. The study was limited by: its small number, single-center experience, and the possibility of missing the diagnosis in some male patients with mild undervirilization.

CONCLUSION

Heterogeneity was noted in the clinical, phenotypic and gonadal features among pediatric patients with 46,XY gonadal dysgenesis.

Tumor risk of children with 45,X/46,XY gonadal dysgenesis in relation to their clinical presentations: Further insights into the gonadal management

OBJECTIVE

To investigate the risk of gonadal germ cell neoplasms (GCN) in children with 45,X/46,XY gonadal dysgenesis and its relation to the clinical presentations.

METHODS

We conducted a retrospective study reviewing the clinical and gonadal features of all consecutive children with 45,X/46,XY gonadal dysgenesis who received gonadal management in a tertiary center from 1985 to 2015. Study subjects were divided into Group I(significant genitalia anomaly), Group II(female phenotype) and Group III(male phenotype).

RESULTS

21 children were studied (Group I=8; Group II=11; Group III=2). All 19 children of Group I and II eventually underwent bilateral gonadectomy. One patient of Group III underwent gonadal biopsy which showed increase in fibrous tissue in the testes without any GCN. 3/8(37.5%) and 6/11(54.5%) of patients in Group I and II respectively had either gonadoblastoma (GB) or carcinoma-in-situ (CIS) or both affecting one or both gonads. Among Group I patients, the 4 dysgenetic testes affected by CIS in 3 patients were intraabdominal (n=1), inguinal (n=1) and scrotal (n=2) in positions. Among Group II patients, 6/20 streak gonads had GB and 2/2 dysgenetic testes had GB or CIS.

CONCLUSIONS

45,X/46,XY children with significant genitalia anomaly or female phenotype are both at high risk of gonadal GCN.

Disorders of sex development: effect of molecular diagnostics

Disorders of sex development (DSDs) are a diverse group of conditions that can be challenging to diagnose accurately using standard phenotypic and biochemical approaches. Obtaining a specific diagnosis can be important for identifying potentially life-threatening associated disorders, as well as providing information to guide parents in deciding on the most appropriate management for their child. Within the past 5 years, advances in molecular methodologies have helped to identify several novel causes of DSDs; molecular tests to aid diagnosis and genetic counselling have now been adopted into clinical practice. Occasionally, genetic profiling of embryos prior to implantation as an adjunct to assisted reproduction, prenatal diagnosis of at-risk pregnancies and confirmatory testing of positive results found during newborn biochemical screening are performed. Of the available genetic tests, the candidate gene approach is the most popular. New high-throughput DNA analysis could enable a genetic diagnosis to be made when the aetiology is unknown or many differential diagnoses are possible. Nonetheless, concerns exist about the use of genetic tests. For instance, a diagnosis is not always possible even using new molecular approaches (which can be worrying for the parents) and incidental information obtained during the test might cause anxiety. Careful selection of the genetic test indicated for each condition remains important for good clinical practice. The purpose of this Review is to describe advances in molecular biological techniques for diagnosing DSDs.

A Newborn with Genital Ambiguity, 45,X/46,XY Mosaicism, a Jumping Chromosome Y, and Congenital Adrenal Hyperplasia

Disorders of sex development (DSD), formerly termed “intersex” conditions, arise from numerous causes. CAH secondary to 21-hydroxylase deficiency is the most common cause of DSD. Sex chromosome disorders, including sex chromosome mosaicism, are the second most common cause of DSD. We discuss a medically complex neonate with DSD presenting with ambiguous genitalia. Hormone levels suggested 21-hydroxylase deficiency. Molecular analysis revealed compound heterozygous mutations in the 21-hydroxylase gene (CYP21A2), confirming the diagnosis of CAH. Chromosome analysis revealed sex chromosome mosaicism with three cell lines: 45,X[8]/45,X,tas(Y;16)(p11.32;p13.3)[8]/45,X,t(Y;8)(p11.32;p23.3)[4] with the Y chromosome in telomere association with chromosomes 8p and 16p in different cell lines, a “jumping translocation.” Histologically, the right gonad had irregular, distended seminiferous tubules with hyperplastic germ cells contiguous with ovarian stroma and primordial follicles. The left gonad had scant ovarian stroma and embryonic remnants. Chromosome analyses showed mosaicism in both gonads: 45,X[17]/45,X,tas(Y;8)(p11.32;p23.3)[3]. This is the first case of coexisting CAH and 45,X/46,XY mosaicism reported in the English literature and the third case of a constitutional chromosome Y “jumping translocation.” Our report documents the medical and genetic complexity of children such as this one with ambiguous genitalia and discusses the need for a multidisciplinary team approach.

45,X mosaicism in northeast China: a clinical report and review of the literature

Purpose

To explore the prevalence and clinical features, especially the reproductive function, of 45,X mosaicism patients in northeast China.

Methods

GTG-banding was performed on a series of 2,250 patients from our genetic counseling clinic. Each of these patients underwent a physical examination and was interviewed about their medical history and reproductive problems. Literature on 45,X mosaicism was accessed using PubMed and reviewed.

Results

The prevalence of 45,X mosaicism in northeast China is 0.36 % (8/2250), and the mosaic karyotype of our study accounted for 61.54 % (8/13) of Turner syndrome cases. This is comparable with studies from Asia, Europe, South America and other regions. The affected patients showed genital abnormalities, abnormal pregnancy or infertility.

Conclusion

45,X mosaicism is commonly seen in the genetic counseling clinic. Extensive cytogenetic assessment may improve the detection rate in patients with congenital dysplasia, or history of abnormal pregnancy or infertility. Karyotyping plays a key role in prognosis and assisted reproduction or early surgical treatment.

Disorders of sexual differentiation: I. Genetics and pathology

Objectives

To provide a summary of the recent major advances in the field of molecular genetics and understanding of psychosexual development, as these developments have resulted in changes in terminology and classification of disorders of sexual differentiation (DSD)/intersex; and to provide a quick and simplified review of the basic information.

Methods

Recent publications (over the last 10 years) were identified by a PubMed search, as were relevant previous studies, using the keywords; ‘sex chromosomes’, ‘psychosexual development’, ‘classifications’, ‘disorders of sexual differentiation’, ‘Chicago consensus’, ‘gonadal malignancy’, ‘intersex’ and ‘ambiguous genitalia’.

Results

The newly proposed terminology and classification has eliminated some confusion for both patient and family, as well as among health professionals. The new advances have facilitated the categorisation of gonadal malignancy in patients with DSD into high-, intermediate- and low-risk groups.

Conclusions

The major changes in terminology and classification of DSD should be considered as the first steps on a long road of research effort. The current available data remain far from sufficient. More molecular genetics studies will allow a better understanding of the causes of each condition of DSD.