Clinical and genetic analysis in males with 46,XX disorders of sex development: A reproductive centre experience of 144 cases

Integration of long-read sequencing, DNA methylation and gene expression reveals heterogeneity in Y chromosome segment lengths in phenotypic males with 46,XX testicular disorder/difference of sex development

BACKGROUND

46,XX testicular disorder/difference of sex development (46,XX DSD) is a rare congenital condition, characterized by a combination of the typical female sex chromosome constitution, 46,XX, and a variable male phenotype. In the majority of individuals with 46,XX DSD, a Y chromosome segment containing the sex-determining region gene (SRY) has been translocated to the paternal X chromosome. However, the precise genomic content of the translocated segment and the genome-wide effects remain elusive.

METHODS

We performed long-read DNA sequencing, RNA sequencing and DNA methylation analyses on blood samples from 46,XX DSD (n = 11), male controls (46,XY; variable cohort sizes) and female controls (46,XX; variable cohort sizes), in addition to RNA sequencing and DNA methylation analysis on blood samples from males with Klinefelter syndrome (47,XXY, n = 22). We also performed clinical measurements on all 46,XX DSD and a subset of 46,XY (n = 10).

RESULTS

We identified variation in the translocated Y chromosome segments, enabling subcategorization into 46,XX DSD (1) lacking Y chromosome material (n = 1), (2) with short Yp arms (breakpoint at 2.7-2.8 Mb, n = 2), (3) with medium Yp arms (breakpoint at 7.3 Mb, n = 1), and (4) with long Yp arms (n = 7), including deletions of AMELY, TBLY1 and in some cases PRKY. We also identified variable expression of the X-Y homologues PRKY and PRKX. The Y-chromosomal transcriptome and methylome reflected the Y chromosome segment lengths, while changes to autosomal and X-chromosomal regions indicated global effects. Furthermore, transcriptional changes tentatively correlated with phenotypic traits of 46,XX DSD, including reduced height, lean mass and testicular size.

CONCLUSION

This study refines our understanding of the genetic composition in 46,XX DSD, describing the translocated Y chromosome segment in more detail than previously and linking variability herein to genome-wide changes in the transcriptome and methylome.

A Case Report on 46,XX Male Difference of Sex Development

The 46,XX male syndrome is a very rare disorder/difference of sex development (DSD). Characterized by a 46,XX karyotype with a male phenotype and various abnormalities, including virilized external genitalia, small testes, hypergonadotropic hypogonadism, and azoospermia. Primarily described in small population studies and clinical reports, much remains to be understood about the prevalence of clinical manifestations, treatment outcomes, and long-term follow-up in this disorder. Here we describe a 24-year-old male who sought medical attention due to a history of erectile dysfunction, associated with a loss of libido, impaired concentration, difficulty sleeping, and bilateral gynecomastia. He and his family had no relevant medical history. On physical examination, the patient had a normal development of secondary sexual characteristics but presented with bilateral testicular atrophy with a volume of 6 ml per testis. A testicular and abdominal ultrasound were performed confirming testicular atrophy and finding no other abnormalities. Laboratory analysis revealed a hypergonadotropic hypogonadism with normal prolactin, thyroid stimulating hormone, hemoglobin, hematocrit, and kidney and liver function. The spermiogram, performed twice, revealed azoospermia. A bone densitometry was also performed, reporting osteopenia in the lumbar spine and left hip. A karyotype test was performed revealing a 46,XX (SRY-positive) DSD. The patient started on therapeutic supplementation with testosterone showing marked improvement of his libido, erectile dysfunction, and return of testosterone to levels within range. The patient and his partner were referred to infertility outpatient care and subsequently opted for in vitro fertilization using a sperm donor. This case report highlights the need for clinical practical awareness of this rare disorder and its wide phenotypical spectrum while also focusing on important aspects of the current literature regarding its approach and treatment. The limited data on long-term management suggest that there is a need for specialized multicenter follow-up not only to ensure a better understanding of this disorder but also to provide a better care on the quality of life and healthy well-being of this patients.

Adult outcomes of urinary, sexual functions and fertility after pediatric management of differences in sex development: Who should be followed and how?

The management of Differences of Sex Development (DSD) has evolved considerably in recent years. The questioning of systematic early childhood treatment of DSD requires a better understanding of the outcomes of such treatments and long-term studies are therefore essential to better evaluate the prognosis of DSD. Unfortunately, limitations are numerous including the limited size of the series, the absence of standardized methodology, the evaluation of managements that no longer take place today and the absence of prospective and comparative studies. Despite these difficulties, the purpose of this paper is to present the current data on the long-term follow-up of patients with DSD from the urological, sexual and fertility points of view. Even if it remains difficult at present to establish precise recommendations, we recapitulate the most important points that should drive follow-up of these patients especially the constitution of a multidisciplinary team with a holistic approach, the organization of the transition between adolescence and adulthood, a particular attention to psychological care, a careful communication with the patients and his/her family and the use of standardized data collection systems.

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

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

Unbalanced X;Y translocations carrying SRY in prenatal settings: Clinical, molecular, and cytogenetic analysis of three cases

BACKGROUND

Generally, the translocation of SRY onto one of the X chromosomes leads to 46, XX testicular disorders of sex development, a relatively rare condition characterized by the presence of testicular tissue with a 46, XX karyotype. Three prenatal cases of unbalanced X; Y translocation carrying SRY were identified in this study.

METHODS

Structural variants were confirmed using single nucleotide polymorphism array and chromosomal karyotyping. X chromosome inactivation (XCI) was also analyzed. Detailed clinical features of the three cases were collected.

RESULTS

We identified two fetuses with maternal inherited unbalanced X; Y translocations carrying SRY and skewed XCI presenting with normal female external genitalia, and one fetus with de novo 46, XX (SRY+) and random XCI manifested male phenotypic external genitalia.

CONCLUSION

This study reports that cases with unbalanced X; Y translocations carrying SRY manifested a normal female external genitalia in a prenatal setting. We speculate that the skewed XCI mediates the silence of SRY. In addition, our study emphasizes that combining clinical findings with pedigree analysis is critical for estimating the prognosis of fetuses with sex chromosome abnormalities.

Long-term outcomes in non-CAH 46,XX DSD

Differences/disorders of sex development (DSD) comprise a large group of rare congenital conditions. 46,XX DSD, excluding congenital adrenal hyperplasia (CAH), represent only a small number of these diseases. Due to the rarity of non-CAH 46,XX DSD, data on this sex chromosomal aberration were confined to case reports or case series with small numbers of patients. As the literature is still relatively sparse, medical data on the long-term effects of these pathologies remain scarce. In this review, we aim to provide an overview of current data on the long-term follow-up of patients with non-CAH 46,XX DSD, by covering the following topics: quality of life, gender identity, fertility and sexuality, global health, bone and cardiometabolic effects, cancer risk, and mortality. As non-CAH 46,XX DSD is a very rare condition, we have no accurate data on adult QoL assessment for these patients. Various factors may contribute to a legitimate questioning about their gender identity, which may differ from their sex assigned at birth. A significant proportion of gender dysphoria has been reported in various series of 46,XX DSD patients. However, it is difficult to give an accurate prevalence of gender dysphoria and gender reassignment in non-CAH 46,XX DSD because of the rarity of the data. Whatever the aetiology of non-CAH 46,XX DSD, fertility seems to be impaired. On the other hand, sexuality appears preserved in 46,XX men, whereas it is impaired in women with MRKH syndrome before treatment. Although there is still a paucity of data on general health, bone and cardiometabolic effects, and mortality, it would appear that the 46,XX DSD condition is less severely affected than other DSD conditions. Further structured and continued multi-center follow-up is needed to provide more information on the long-term outcome of this very rare non-CAH 46,XX DSD condition.

Early Diagnosis of 46,XX Testicular Difference of Sexual Development: Unusual Presentation with Increased Nuchal Translucency

INTRODUCTION

46,XX testicular disorder of sexual development (DSD) may present prenatally as a mismatch between phenotype and karyotype. Enlarged nuchal translucency is an abnormal sign of many disorders. We present a first trimester fetus with increased nuchal translucency that was later determined to be a 46,XX testicular DSD.

CASE PRESENTATION

A first-trimester pregnancy ultrasound revealed enlarged nuchal translucency. Chorionic villous sampling documented a 46,XX karyotype. Subsequent ultrasounds identified male external genitalia. FISH analysis documented a SRY gene translocation. At birth, the infant had normal male internal and external genitalia.

CONCLUSIONS

46,XX testicular DSD may present in the first trimester with an enlarged nuchal translucency.

XX Male: Early Detection With Prenatal Testing

A 46,XX male represents a variant of Klinefelter syndrome (47,XXY), under the category of a disorder of sex development (DSD). Despite possessing an XX karyotype, these individuals exhibit a male phenotype, which, in this case, results from a translocation of the SRY gene from the Y chromosome onto the X chromosome. This genetic alteration results in the development of male gonadal characteristics. This case report outlines a prenatal diagnosis of a 46,XX female in conflict with a level 2 ultrasound. It details the patient's presentation, diagnosis of an SRY-positive 46,XX male, and medical history. The discussion focuses on the advantages of early identification and intervention in managing symptom progression and addressing fertility challenges through hormone replacement therapy. Further exploration of 46,XX DSD early detection and the underlying mechanisms is essential for refining diagnostic and therapeutic approaches that result in a greater quality of life for these patients.

A rare case of male sex reversal syndrome (46, XX) with negative SRY gene: a disorder of sexual differentiation (DSD)

Background

Male sex reversal syndrome is a rare genetic cause of male infertility with an overall incidence of 1/20,000–1/100,000 males. There is mismatching between the genetic make-up and the apparent clinical features. The clinical presentation of such cases is variable ranging from ambiguous genitalia at birth, failed puberty, up to normal male phenotype with infertility and hypogonadism. The exact molecular and genetic bases of this syndrome are still unclear. Most of the recorded cases were SRY positive (i.e. representing 80–90% of all cases), and they showed translocated SRY gene on the Y chromosome. Moreover, fewer cases of male sex reversal (46, XX) were SRY negative.

Case presentation

Herby, we report a rare case of a 35-year-old infertile male patient who presented with azoospermia, hypergonadotropic hypogonadism, and abnormal classical (46, XX) karyotype, as well as negative FISH for SRY gene. He had a previous negative biopsy and was asking for redoing micro-TESE, whoever he was discouraged as chances to find sperm is eventually nil, and instead, he was prescribed testosterone replacement therapy to correct hypogonadism.

Conclusion

Therefore, any case of non-obstructive azoospermia should be offered genetic testing trying to exclude non-treatable cases and for genetic counseling.

SRY-Positive 46, XX Testicular Disorder of Sexual Development With Leydig Cell Tumor

The risk of a gonadal tumor is high in testicular disorder of sexual development (DSD) with the Y chromosome, but cases of DSD without the Y chromosome are extremely rare. We reported a gonadal tumor in a phenotypically male individual with 46, XX testicular DSD. A testicular tumor was incidentally found in a 32-year-old phenotypic male who was presented to the hospital with male infertility. A diagnosis of 46, XX testicular DSD was made by the presentation of karyotype analysis of 46, XX with the sex-determining region of the Y chromosome (SRY) positive and gonadal tissue without female gonads. Surgery was performed due to a gradually growing tumor. The partial orchidectomy was performed with the diagnosis of a benign Leydig cell tumor in frozen biopsy.

Application of FF-QuantSC for the Precise Estimation of Fetal Fraction in Non-invasive Prenatal Testing in Two SRY-Translocation Cases

Background: Non-invasive prenatal testing (NIPT) is a commonly employed clinical method to screen for fetal aneuploidy, while the Y chromosome-based NIPT method is regarded as the gold standard for the estimation of fetal fraction (FF) of male fetuses. However, when the fetus has a derivative Y chromosome thereby containing a partial Y chromosome, the Y chromosome-based NIPT method cannot accurately calculate FF. Therefore, alternative methods to precisely calculate FF are required.

Methods: Two prenatal cases could not be detected effectively using the Y chromosome-based NIPT method because of low FF. According to the Y chromosome-based method, the FF of the fetuses were 1.730 ± 0.050% (average gestation week: 18⁺¹) and 2.307 ± 0.191% (average gestation week: 20⁺⁰) for cases 1 and 2, respectively. Using various genetic diagnostic techniques, including the BoBs™ assay, karyotype analysis, improved nucleolus-organizing region (NOR)-banding analysis, Affymetrix CytoScan 750K Array, and fluorescence in situ hybridization (FISH) analysis, we determined the genetic defects of two fetuses with translocations of the SRY locus. Further, we reassessed the FF using FF-QuantSC and X chromosome-based methods. The distribution diagram of reads for chromosome Y was also analyzed.

Results: The FF of the fetuses determined by FF-QuantSC were 10.330% (gestation week: 18⁺⁴) in case 1 and 9.470% (gestation week: 21⁺⁴) in case 2, while the FF of the fetuses determined using the X chromosome-based method were 8.889% (gestation week: 18⁺⁴) in case 1 and 2.296% (gestation week: 21⁺⁴) in case 2. Both the distribution diagrams of reads for chromosome Y of the two cases showed the deletion in the long arm of the Y chromosome.

Conclusion: For repeatedly low FF samples detected using the Y chromosome-based NIPT method for a long gestational week, we believe that FF-QuantSC and distribution diagrams of reads could be used as a supplement to NIPT, especially for rare cases of sex reversal caused by SRY translocation.

46, XX Ovotesticular disorder of sex development (true hermaphroditism) with seminoma: A case report

RATIONALE

Ovotesticular disorder of sex development (DSD), previously known as true hermaphroditism, is a disorder in which individuals have both testicular and ovarian tissues. Instances of tumors arising in the gonads of individuals with 46,XX ovotesticular DSD are uncommon.

PATIENT CONCERNS

We report a case of a 36-year-old phenotypical male with a chief complaint of an abdominal mass for 3 months. He reported normal erections and regular menses. Computerized tomography showed a large tumor measuring 15 × 10 cm in size, a uterus, and a cystic ovary.

DIAGNOSIS

46, XX ovotesticular DSD with seminoma.

INTERVENTIONS

The patient was treated with neochemotherapy (etoposide and cisplatin), surgery, chemotherapy, and testosterone replacement.

OUTCOMES

At the 13-month follow-up, the patient reported satisfactory erections, and no evidence of disease was found.

CONCLUSION

Cases of 46,XX ovotesticular DSD with seminoma are uncommon. Our case reveals the importance of surgery combined with neochemotherapy, chemotherapy, and testosterone replacement in these patients to improve the prognosis.

Multiscale analysis of SRY-positive 46,XX testicular disorder of sex development: Presentation of nine cases

46,XX testicular disorder of sex development (46,XX TDSD) is a relatively rare condition characterised by the presence of testicular tissue with 46,XX karyotype. The present study aims to reveal the phenotype to genotype correlation in a series of sex-determining region Y (SRY)-positive 46,XX TDSD cases. We present the clinical findings, hormone profiles and genetic test results of six patients with SRY-positive 46,XX TDSD and give the details and follow-up findings of our three of previously published patients. All patients presented common characteristics such as azoospermia, hypergonadotropic hypogonadism and an SRY gene translocated on the terminal part of the short arm of one of the X chromosomes. Mean ± standard deviation (SD) height of the patients was 164.78 ± 8.0 cm. Five patients had decreased secondary sexual characteristics, and three patients had gynaecomastia with varying degrees. Five of the seven patients revealed a translocation between protein kinase X (PRKX) and inverted protein kinase Y (PRKY) genes, and the remaining two patients showed a translocation between the pseudoautosomal region 1 (PAR1) of X chromosome and the differential region of Y chromosome. X chromosome inactivation (XCI) analysis results demonstrated random and skewed XCI in 5 cases and 1 case, respectively. In brief, we delineate the phenotypic spectrum of patients with SRY-positive 46,XX TDSD and the underlying mechanisms of Xp;Yp translocations.

Possible misdiagnosis of 46,XX testicular disorders of sex development in infertile males

Objectives: The 46,XX disorders of sex development (DSD) is a rare genetic cause of male infertility and possible misdiagnosis of this condition has never been reported. We aim to investigate clinical characteristics and laboratory results of infertile males with possibly misdiagnosed 46,XX DSD. Methods: Between January 2008 and December 2017, a retrospective case series study was performed involving sixteen 46,XX DSD males without azoospermia factor (AZF) deletion. Demographics, clinical features, laboratory results and assisted reproductive technology (ART) outcomes of these patients were depicted, and the underlying accurate diagnosis was also discussed. Results: The mean age was 30.06 ± 5.40 years old. Thirteen patients (81.25%) merely obtained secondary school education. Gynaecomastia occurred in one case, and cryptorchidism appeared in two cases. Testicular volumes were equal to 15 mL on two sides in one patient who had severe asthenozoospermia. Thirteen patients (81.25%) had bilateral atrophic testes which were below 5 mL. The majority of patients were observed with elevated levels of gonadotropic hormones and decreased testosterone values. Neither AZF region nor sex-determining region Y gene was absent among all patients. Twelve patients had normal ejaculatory function, whereas four were diagnosed with ejaculatory dysfunction. Eleven patients (68.75%) were diagnosed with azoospermia. Testicular sperm aspiration was performed in six subjects (37.50%). The pathological results showed that Leydig cell hyperplasia with spermatic failure was found in each case, and no sperm was found in testicular tissue. ART with donor sperm was conducted in 15 patients. Live birth was achieved in three cases through artificial insemination by donor and in one case using in-vitro fertilization by donor. Conclusions: Chromosomal analysis rarely yields 46,XX karyotype combined with no deletion of AZF in infertile males. Under this condition, molecular analysis should be conducted to avoid potential misdiagnosis and false interpretation of other findings.

46,XX male disorder of sexual development

An individual’s sexual phenotype is usually determined by the presence or absence of the Y chromosome in the embryo’s karyotype, however, due to abnormal X/Y terminal exchange through male meiosis, a few individuals develop male genitalia in the absence of the Y chromosome. This case report presents an adolescent referred to the Pediatric Endocrinology Unit due to bilateral gynecomastia. A diagnosis of hypergonadotropic hypogonadism was established and chromosomal analysis disclosed 46,XX karyotype, with the SRY gene locus found on one of his X chromosomes. A multidisciplinary approach, including psychological support and genetic counseling, is ideal for the management of these patients. Neoplastic transformation of the dysgenetic gonads has been described in several cases, and hence self-examinations and regular ultrasounds are commonly advised.