XY Complete Gonadal Dysgenesis Research Articles

Swyer Syndrome: An in-Depth Exploration of Phenotypic and Genotypic Features in 46, XY Disorders of Sex Development

Swyer Syndrome, also known as 46, XY Complete Gonadal Dysgenesis, is a rare and intriguing disorder of sexual development characterized by a phenotypic female appearance in individuals possessing a 46,XY karyotype. This enigmatic condition results from a cascade of genetic and hormonal events, which ultimately lead to the absence of functional gonads, presenting a challenging diagnostic and therapeutic conundrum. In this comprehensive review, we delve into the intricate landscape of Swyer syndrome, elucidating its genetic underpinnings, clinical manifestations, diagnostic approaches, and contemporary management strategies. By consolidating current knowledge, this article aims to provide a valuable resource for healthcare professionals, geneticists, and researchers interested in unraveling the complexities of disorders of sex development and the genetic determinants of sexual differentiation.

Gonadal tumor risk in pediatric and adolescent phenotypic females with disorders of sex development and Y chromosomal constitution with different genetic etiologies.

ObjectivesThis retrospective study sought to investigate the risk and proportion of gonadal neoplasms in phenotypic female pediatric patients with DSD and the presence of the Y chromosome and different genetic backgrounds in a single Chinese center.Materials and MethodsFrom January 2012 to December 2020, pediatric and adolescent patients with DSD and the presence of the Y chromosome who had unambiguous female genitalia and underwent bilateral gonadectomy or gonadal biopsy were included in this study. Patients’ demographics, karyotype, laboratory test results, gross pathology, and histology of gonadal tissue were all collected. The patients were divided into three groups based on their different genetic backgrounds, and the percentage of gonadal tumors was calculated to assess the risk of gonadal tumor and malignancy by etiology.ResultsA total of 22 patients with DSD and an unambiguous female phenotype with a Y chromosome were recruited. The mean age was 10.91 ± 4.99 years (9 months to 19 years). Gonadal neoplasia was confirmed in six (27.3%) cases by pathological examination of surgical gonadal tissue samples. Among 44 gonadal samples from these 22 patients, the following were identified: five gonadoblastomas, three dysgerminomas, and two Leydig cell tumors. The youngest patient with a tumor was a 2-year-old girl with 46,XY complete gonadal dysgenesis (46,XY CGD or Swyer syndrome) and bilateral gonadoblastoma. Patients with 46,XY complete gonadal dysgenesis (4/6; 66.7%) had the highest tumor occurrence rate. Among 10 patients with Turner syndrome with the presence of the Y chromosome, only one patient was diagnosed with a gonadal tumor. Leydig cell tumor was diagnosed in only one of six patients with 46,XY androgen synthesis/action disorders.ConclusionPediatric patients with 46,XY complete gonadal dysgenesis had a significantly increased risk of developing gonadal tumors and underwent prophylactic gonadectomy as soon as the diagnosis was confirmed, whereas those with Turner syndrome with Y chromosome and 46,XY androgen synthesis/action disorders had a relatively low risk. In view of the limited number of patients, a large multicenter study with close follow-ups is needed to support these conclusions.

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

ObjectiveInfertility 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 MeasuresA 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. ResultsCompleted 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. ConclusionsMany 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.

Swyer syndrome (46, XY complete gonadal dysgenesis): A rare case of primary amenorrhea

Swyer syndrome is a type of gonadal dysgenesis wherein a 46,XY karyotype presents with a female phenotype. It is a rare cause of disorder in sexual development that occurs in 1:100,000 births. Local studies are currently limited to few case reports. Sex-determining region on the Y chromosome gene mutation is the root cause of nonfunctional gonads with no hormonal or reproductive potential. They are born with normal female external genitalia but not suspected until puberty when menses do not occur or if secondary sexual characteristics do not develop. This report presents the case of a 23-year-old phenotypically female presenting with primary amenorrhea and hypogastric discomfort. Ultrasound revealed an infantile cervix and uterus with streak left ovarian tissue and a cystic mass on the right pelvic area. Gonadotropin levels were elevated, and the karyotype showed a normal male 46,XY. Laparoscopic bilateral gonadectomy with salpingectomy was done, which revealed dysgerminoma on bilateral ovarian tissues. In conclusion, this report describes a rare case of Swyer syndrome associated with ovarian dysgerminoma. Accurate and prompt diagnosis, using a systematic approach in evaluating primary amenorrhea, is crucial in initiating treatment. Our goal is to ensure hormonal replacement, fertility preservation, psychosexual and emotional stress reduction, and overall patient survival.

Expanding the spectrum of syndromic PPP2R3C-related XY gonadal dysgenesis to XX gonadal dysgenesis.

Homozygous variants in PPP2R3C have been reported to cause a syndromic 46,XY complete gonadal dysgenesis phenotype with extragonadal manifestations (GDRM, MIM# 618419) in patients from four unrelated families, whereas heterozygous variants have been linked to reduced fertility with teratozoospermia (SPGF36, MIM# 618420) in male carriers. We present eight patients from four unrelated families of Turkish and Indian descent with three different germline homozygous PPP2R3C variants including a novel in-frame duplication (c.639_647dupTTTCTACTC, p.Ser216_Tyr218dup). All patients exhibit recognizable facial dysmorphisms allowing gestalt diagnosis. In two 46,XX patients with hypergonadotropic hypogonadism and nonvisualized gonads, primary amenorrhea along with absence of secondary sexual characteristics and/or unique facial gestalt led to the diagnosis. 46,XY affected individuals displayed a spectrum of external genital phenotypes from ambiguous genitalia to complete female. We expand the spectrum of syndromic PPP2R3C-related XY gonadal dysgenesis to both XY and XX gonadal dysgenesis. Our findings supported neither ocular nor muscular involvement as major criteria of the syndrome. We also did not encounter infertility problems in the carriers. Since both XX and XY individuals were affected, we hypothesize that PPP2R3C is essential in the early signaling cascades controlling sex determination in humans.

Cytogenetic and molecular characterization in gonadal tissue of patients with ovotesticular syndrome and gonadal dysgenesis 46,XY and 46,XX

Abstract Objectives: Etiology of gonadal dysgenesis and ovotesticular syndrome is unknown in a majority of cases. To perform cytogenetic and molecular characterization of a group of patients with ovotesticular syndrome and complete gonadal dysgenesis from peripheral blood and gonadal tissue samples. Materials and methods: A total of 6 patients were included, 3 with diagnosis of 46,XX ovotesticular syndrome, one diagnosed with 46,XY ovotesticular syndrome; one with suspected 46,XX gonadal dysgenesis, and one with 46,XY complete gonadal dysgenesis. Results: All patients were evaluated with karyotype, fluorescent in situ hybridization (FISH) for SRY, multiplex ligation-dependent probe amplification (MLPA) and comparative genomic hybridization (aCGH) on peripheral blood samples. In cases with available gonadal tissue, the levels of genetic expression of SOX3, SRY, and SOX9 were determined through real-time PCR and immunofluorescence. Rearrangements involving SRY gene were ruled out. No deletions/duplications or copy-number variations (CNV) were detected as the etiology for sexual development disorder in any of the patients studied. In a case of 46,XX ovotesticular syndrome, the gonadal karyotype was different from the karyotype in peripheral blood. Aberrant expression of SOX3 and SOX9 in gonadal tissue of a case with 46,XX ovotesticular syndrome was observed. Conclusions: Lower levels of expression of SRY and SOX9 compared to the levels in human cellular lines of embryonic testicle and Sertoli were documented in the gonadal tissue of a case with 46,XY ovotesticular syndrome. Cytogenetic and molecular studies of the gonads as a complement to peripheral blood study have the potential to enrich the understanding of sexual development disorders in patients who are XX or XY in peripheral blood.

Cytogenetic and molecular characterization in gonadal tissue of patients with ovotesticular syndrome and gonadal dysgenesis 46,XY and 46,XX

Abstract 
 Objectives: Etiology of gonadal dysgenesis and ovotesticular syndrome is unknown in a majority of cases. To perform cytogenetic and molecular characterization of a group of patients with ovotesticular syndrome and complete gonadal dysgenesis from peripheral blood and gonadal tissue samples.
 Materials and methods: A total of 6 patients were included, 3 with diagnosis of 46,XX ovotesticular syndrome, one diagnosed with 46,XY ovotesticular syndrome; one with suspected 46,XX gonadal dysgenesis, and one with 46,XY complete gonadal dysgenesis.
 Results: All patients were evaluated with karyotype, fluorescent in situ hybridization (FISH) for SRY, multiplex ligation-dependent probe amplification (MLPA) and comparative genomic hybridization (aCGH) on peripheral blood samples. In cases with available gonadal tissue, the levels of genetic expression of SOX3, SRY, and SOX9 were determined through real-time PCR and immunofluorescence.
 Rearrangements involving SRY gene were ruled out. No deletions/duplications or copy-number variations (CNV) were detected as the etiology for sexual development disorder in any of the patients studied. In a case of 46,XX ovotesticular syndrome, the gonadal karyotype was different from the karyotype in peripheral blood. Aberrant expression of SOX3 and SOX9 in gonadal tissue of a case with 46,XX ovotesticular syndrome was observed.
 Conclusions: Lower levels of expression of SRY and SOX9 compared to the levels in human cellular lines of embryonic testicle and Sertoli were documented in the gonadal tissue of a case with 46,XY ovotesticular syndrome. Cytogenetic and molecular studies of the gonads as a complement to peripheral blood study have the potential to enrich the understanding of sexual development disorders in patients who are XX or XY in peripheral blood.

Expanding DSD Phenotypes Associated with Variants in the DEAH-Box RNA Helicase DHX37

Missense variants in the RNA-helicase DHX37 are associated with either 46,XY gonadal dysgenesis or 46,XY testicular regression syndrome (TRS). DHX37 is required for ribosome biogenesis, and this subgroup of XY DSD is a new human ribosomopathy. In a cohort of 140 individuals with 46,XY DSD, we identified 7 children with either 46,XY complete gonadal dysgenesis or 46,XY TRS carrying rare or novel DHX37 variants. A novel p.R390H variant within the RecA1 domain was identified in a girl with complete gonadal dysgenesis. A paternally inherited p.R487H variant, previously associated with a recessive congenital developmental syndrome, was carried by a boy with a syndromic form of 46,XY DSD. His phenotype may be explained in part by a novel homozygous loss-of-function variant in the NGLY1 gene, which causes a congenital disorder of deglycosylation. Remarkably, a homozygous p.T477H variant was identified in a boy with TRS. His fertile father had unilateral testicular regression with typical male genital development. This expands the DSD phenotypes associated with DHX37. Structural analysis of all variants predicted deleterious effects on helicase function. Similar to all other known ribosomopathies, the mechanism of pathogenesis is unknown.

Swyer Syndrome, 46, XY complete gonadal dysgenesis in a patient with spontaneous menarche

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

59. Tamoxifen for Puberty Induction and Bone Mineral Density Protection in a Gender Non Binary Patient With 46, XY Complete Gonadal Dysgenesis: A Case Report

<h3>Background</h3> 46XY complete gonadal dysgenesis patients present with primary amenorrhea and delayed puberty. There is an increased risk of gonadoblastoma and often undergo surgical resection. Following diagnosis, sex hormone replacement therapy is started for puberty induction. Tamoxifen prevents loss of bone mineral density in postmenopausal women and has been used to treat gynecomastia in prepubertal males. We present a case of a nonbinary patient with 46XY complete gonadal dysgenesis where typical sex hormone replacement therapy would be incongruent with the patient's gender identity and instead, tamoxifen was used for puberty induction and bone health protection. <h3>Case</h3> A 15 year old patient with autism and ADHD presented with primary amenorrhea. Breast development occurred 1.5 years prior without development of pubic or axillary hair. They had previously identified as gender neutral. They had an elevated FSH (51mIU/mL), elevated LH (16mIU/mL), low estradiol (<2.5pg/mL), low testosterone (10ng/dL), and karyotype 46XY SRY+ of unknown molecular etiology. Sonography showed a prepubertal uterus (4.5 × 0.5 × 2.5cm) and intraabdominal gonads. The workup was suggestive of 46XY complete gonadal dysgenesis. DEXA scan showed decreased bone mineral density for chronologic age (Z score -2.3, whole body BMD:0.71 g/cm2). They were counseled regarding the risk of gonadoblastoma in intraabdominal gonads and elected to undergo a laparoscopic gonadectomy. They expressed concerns about sex hormone replacement and did not wish to develop secondary sex characteristics that would be incongruent with their nonbinary identity. A selective estrogen receptor modulator (tamoxifen) was started for bone health protection without the development of secondary sex characteristics. At 4 months, their height had increased 2cm and had a reduction in breast tissue. At 1 year, their height had increased 5cm and the increase in growth velocity showed pubertal induction. Repeat ultrasound demonstrated a uterus size of 6 × 1.3 × 2.2 cm and a non-visualized endometrial stripe. DEXA showed improvement (Z score -2.2, whole body BMD:0.81 g/cm2). Tamoxifen was titrated up to a goal dose of 15-20mg daily. Mental health and psychosocial adaptation was regularly screened following the DSD-TRN protocol. The patient has not had any menstrual bleeding, continues on the tamoxifen, and plans to undergo a hysterectomy at the age of 18. <h3>Comments</h3> Following gonadectomy in patients with 46XY complete gonadal dysgenesis, hormone replacement therapy is imperative for overall heath, puberty induction, and bone health. In patients who require sex hormone replacement but whose gender is not consistent with a male or female gender identity, a selective estrogen receptor modulator can be used.

Association between Down Syndrome and Disorders of Sex Development: Report of Three Cases and Review of 188 Cases in the Literature

In this study, we present 3 cases of Down syndrome (DS) associated with disorders/differences of sex development (DSD) and review the literature on this topic. Case 1: 1-year-old child with male genitalia and DS phenotype, 47,XX,+21 karyotype and testicular DSD. Case 2: 11-month-old child with male genitalia and few DS dysmorphisms, 45,X/47,XY,+21 karyotype, and mixed gonadal dysgenesis. Case 3: 4-month-old child with female genitalia and DS phenotype, 47,XY,+21 karyotype and XY complete gonadal dysgenesis. In the literature, among 188 patients, 107 (57%) had Klinefelter syndrome and 61 (33%) Turner syndrome, 12 (6%) had mixed gonadal dysgenesis, 2 (1%) had partial androgen insensitivity, 2 (1%) ovotesticular DSD, and the others had congenital adrenal hyperplasia, XY partial gonadal dysgenesis, XY complete gonadal dysgenesis, and complete androgen insensitivity (1 case each). A typical DS phenotype was found in all individuals of the revision, with the exception of one case, but DSD features were not always reported. In conclusion, the association of DS with sex chromosome DSD is the most frequently observed, whereas associations with 46,XX and 46,XY DSD is extremely rare.

Frasier Syndrome: A Rare Disorder in a Patient With Nephrotic Syndrome

Frasier syndrome is a rare genetic disorder characterized by the association of progressive renal glomerulopathy, 46,XY complete gonadal dysgenesis with a high risk of developing gonadoblastoma. Mutations in the Wilms' tumor suppressor gene (WT1) located in 11p23 responsible for this syndrome. Patients with this syndrome commonly present with normal female genitalia, streak gonads, and 46, XY karyotyping. Nephropathy in Frasier syndrome conferred as a nephrotic syndrome (NS) with proteinuria that begins early in childhood and progressively increases with age, mainly due to nonspecific focal and segmental glomerular sclerosis (FSGS). We herein discuss a 4 year-old-girl who presented as a steroid-resistant nephrotic syndrome and later on diagnosed as a Frasier syndrome.

Disorders of Sexual Development: Presentation and Categorization at Allied Hospital / Punjab Medical College Faisalabad, Pakistan

Background: Ambiguous genitalia is a condition in which external genitalia of the patients are ambiguous (not clearly male or female) or their external genitalia do not match with the chromosomal sex. It’s a rare condition and its incidence is 1.7%, or others say 1/5500 live births. Current nomenclature defines it as “disorder of sexual development” (DSD). It is generally divided into six categories; 46 XY DSD,46 XX DSD, chromosomal DSD, ovo-testicular DSD, 46 XY complete gonadal dysgenesis & 46XX testicular DSD. I_DSD registry (Glasgow) is the largest organization which registers such cases for clinical research and standardizes the information. Data from 51 centers from 36 countries across the globe is being uploaded there. Urology Department of Allied Hospital Faisalabad is the only center from Pakistan which registers its cases. Objectives: To identify and categorize different presentations of DSD according to the standard nomenclature. 2-To register the cases of DSD to I-DSD registry in Glasgow to be included in further clinical research. Study Design: Retrospective study. Settings: Urology Department Allied Hospital Faisalabad, Pakistan. Duration: From 01-09-2008 to 31-08-2019. Inclusion Criteria: All the patients with indeterminate sex / ambiguous genitalia presenting to OPD of Allied hospital Faisalabad irrespective of age Exclusion Criteria: Patients previously operated for DSD / with unrecorded data at first presentation. Methodology: Relevant data was retrieved from patients’ charts taken from hospital records, with the permission of hospital administration to publish their data. Patients had been evaluated with history/examination for phenotypical sex, with karyotyping for chromosomal sex, and ultrasonography & hormonal analysis (serum testosterone, FSH, LH and Estradiol) for gonadal sex. Specific tests like 17-OH levels performed in selected patients (CAH). Gender assignment was done according to chromosomal sex, after counselling of parents and adult patients. Results: Total 34 patients were enrolled. Mean age at presentation was 16.38 ± 9.38 years (range 10 months to 42 years). Nine of 34 patients were brought up as females, one as intersex and 24 as males. After categorization of various clinical presentations according to standard nomenclature, 27(79.4%) belonged to 46XY DSD category, 03(8.80%) to 46XX DSD, 02 (5.88%) to chromosomal DSD, 01(2.90%) was 46XY complete gonadal dysgenesis and 01(2.90%) patient belonged to ovo-testicular DSD. None of the patients had 46XX testicular DSD. Among the presumed female patients, six were chromosomally male and were having perineal hypospadias and were later assigned the male gender. Among the presumed male patients, two were diagnosed as CAH patients with XX genetic makeup. Three patients were having exstrophy epispadias complex, 15 patients were having perineal hypospadias (majority with undescended testes) and 7 had penoscrotal hypospadias. Conclusion: Identification & categorization of indeterminate sex and gender assignment is mandatory for social & psychological well-being of patients and their families.

CLINICAL CASE OF A SUCCESSFUL PREGNANCY WITH THE COMPLETE FORM OF GONADAL DYSGENESIS - SWYER SYNDROME

Swyer syndrome (46,XY complete gonadal dysgenesis) is a rare chromosomal pathology. This pathology occurs with a frequency of 1 in 80,000. In genetic analysis, mutations are most often found in the following genes: the SRY gene, the NR5A1 gene, the SOX9 gene, the MAP3K1 gene. Patients with this disease develop phenotypically as women, but due to the absence of gonads and eggs, independent pregnancy is impossible. This article describes a clinical case of a successful onset, course of pregnancy and delivery in a woman with Swyer syndrome using assisted reproductive technology.

Early-Onset Gonadoblastoma in a 13-Month-Old Infant with 46,XY Complete Gonadal Dysgenesis Identified with Prenatal Testing: A Case of Chromosome 9P Deletion

Individuals with 46,XY complete gonadal dysgenesis (CGD) are at high risk of developing gonadal neoplasms. Chromosome 9p monosomy with deletion of the DMRT1 gene, a key transcription factor in testicular development, is one of the known causes of 46,XY CGD. Noninvasive prenatal testing (NIPT) is being increasingly used, and can identify disorders of sexual development (DSDs). We report the case of a 46,XY infant with phenotypically female external genitalia, müllerian structures including uterus and fallopian tubes, and bilateral streak gonads who was found to have unilateral gonadoblastoma at 13 months. 46,XY DSD was suggested prenatally when discordance between NIPT and fetal ultrasound was noted. Genetic investigation revealed a deletion of 12.5 million base pairs at chromosome 9p24.3, which includes the doublesex and MAB-3-related transcription factor-1 (DMRT1) gene. Current guidelines recommend gonadectomy at the time of diagnosis in cases of 46,XY CGD, and our patient had gonadoblastoma at 13 months. 46,XY DSD, including rare disorders such as CGD, will be increasingly identified before birth with more widespread use of NIPT, raising the question about the appropriate timing of gonadectomy in prenatal diagnoses. Our case supports the current recommendation to perform gonadectomy as early as possible after diagnosis.

Novel pathogenic mutations in disorders of sex development associated genes cause 46,XY complete gonadal dysgenesis

Disorders of sex development (DSDs) are congenital conditions in which chromosomal, gonadal and sex is atypical. It is difficult to diagnose and manage patients with DSD in clinical practice, and the molecular etiology of DSD is still not completely understood. Here, we identified two novel pathogenic mutations from three unrelated Chinese patients with 46,XY complete gonadal dysgenesis (CGD) that is a clinical subgroup of DSD by whole exome sequencing. A novel mutation in the SRY gene (c.161delG) was identified in the first patient, and the second patient carried a novel missense mutation in the MAP3K1 gene (c.2117T>G). Bioinformatics analysis found that the deletion of SRY (c.161delG) led to a premature stop codon at amino acid 59 in the SRY protein, which resulted in lacking the DNA binding domain of SRY protein. Functional studies found that the missense mutation in the MAP3K1 gene (c.2117T>G) could interfere with the gene function through increasing the phosphorylation of the downstream targets of MAP3K1, ERK1/2 and p38, which resulted in reducing testis-determining factor SOX9 expression and increasing ovary-promoting factor β-catenin activity. According to the American college of medical genetics and genomics (ACMG) standards and guidelines, these mutations were categorized as “pathogenic” mutations. Thus, our findings provide two novel pathogenic mutations associated with 46,XY CGD that can improve the etiological diagnosis for 46,XY CGD. AbbreviationsUnlabelled TableACMGAmerican college of medical genetics and genomicsATRXalpha thalassemia/mental retardation syndrome X-linkedCADDcombined annotation dependent depletionCBX2chromobox 2CGDcomplete gonadal dysgenesisCTNNB1catenin beta 1DHHdesert hedgehogDSDdisorders of sex developmentEVSexome variant serverFATHMMfunctional analysis through hidden markov modelsFSHfollicle stimulating hormoneHGMDhuman gene mutation databaseHMGhigh mobility groupLHluteinizing hormoneMAP3K1mitogen activated protein kinase kinase kinase 1M-CAPmendelian clinically applicable pathogenicityNR5A1nuclear receptor subfamily 5 group A member 1PCRpolymerase chain reactionPolyPhen-2polymorphism phenotyping v2PROVEANprotein variation effect analyzerqRT-PCRquantitative reverse transcription PCRSIFTsorting intolerant from tolerantSOX9SRY box related 9SRYsex determining region of the Y chromosomeWNT4wingless type MMTV integration site family member 4WT1wilms tumor 1ZNRF3zinc/RING finger protein 3

Genetic etiology of 46, XY complete gonadal dysgenesis

46, XY complete gonadal dysgenesis(46, XY CGD)is a rare congenital genetic disease.Individuals with 46, XY CGD are characterized by female external genitalia, Mullerian duct structures and streak gonads.The pathogenesis of this disease is complex, which is related to the variation of sex determination genes in humans.In addition to the classic genes SRY, SOX9 and NR5A1, it has been found that the disease can be caused by the signal pathways such as DHH and MAPK, as well as other regulatory factors such as ubiquitination in recent years.However, only less than 50% of patients receive an accurate clinical genetic diagnosis.Facilitated by ongoing developments in genetic sequencing technologies, more and more potential pathogenic genes have been discovered, enriching the gene regulatory network of sex determination.The proper and prompt diagnosis and treatment of 46, XY CGD are always challenging, given the low rate of diagnosis and the risk of gonadal malignancy, which are imperative for long-term management of the individuals.Recently, great progress has been made in the study of 46, XY CGD both at home and abroad. Key words: Disorders of sex development; Gonadal development; Gene; Signaling pathways

Functional Analysis of Mutations at Codon 127 of the SRY Gene Associated with 46,XY Complete Gonadal Dysgenesis

Complete gonadal dysgenesis (CGD) is characterized by an incomplete differentiation of the genital organs in a patient with a 46,XY karyotype. It is induced by mutations in the sex-determining region Y (SRY) gene which plays a key role in testis-determining pathways. The aim of this study was to investigate the possible pathogenic nature of a novel SRY mutation (p.Y127H) identified in a 46,XY female patient. To determine the effect of this mutation on SRY function, we studied its impact on DNA interaction by electrophoretic mobility shift assays. Since tyrosine 127 is close to the C-terminal nuclear localization signal of SRY, we conducted HA-SRY protein expression to observe the impact of the mutation on the nuclear import function in transfected cells. Our results showed that the Y127H mutation nearly abolishes the DNA-binding capacity of SRY and strongly impairs the nuclear localization of the mutated protein. Together with a previously described mutation analyzed in parallel in this paper (p.Y127C), our results highlight this tyrosine residue as a crucial structural determinant of the high mobility group box domain. This is the first report to explain the molecular mechanism of the Y127H mutation causing sex reversal and gives new insights for clinical practice to benefit patients with disorders of sex development.

Stochastic anomaly of methylome but persistent SRY hypermethylation in disorder of sex development in canine somatic cell nuclear transfer.

Somatic cell nuclear transfer (SCNT) provides an excellent model for studying epigenomic reprogramming during mammalian development. We mapped the whole genome and whole methylome for potential anomalies of mutations or epimutations in SCNT-generated dogs with XY chromosomal sex but complete gonadal dysgenesis, which is classified as 78, XY disorder of sex development (DSD). Whole genome sequencing revealed no potential genomic variations that could explain the pathogenesis of DSD. However, extensive but stochastic anomalies of genome-wide DNA methylation were discovered in these SCNT DSD dogs. Persistent abnormal hypermethylation of the SRY gene was observed together with its down-regulated mRNA and protein expression. Failure of SRY expression due to hypermethylation was further correlated with silencing of a serial of testis determining genes, including SOX9, SF1, SOX8, AMH and DMRT1 in an early embryonic development stage at E34 in the XYDSD gonad, and high activation of the female specific genes, including FOXL2, RSPO1, CYP19A1, WNT4, ERα and ERβ, after one postnatal year in the ovotestis. Our results demonstrate that incomplete demethylation on the SRY gene is the driving cause of XYDSD in these XY DSD dogs, indicating a central role of epigenetic regulation in sex determination.

A novel mutation in the SRY gene of a Chinese 46, XY female patient with unilateral mixed germ cell tumor

Objective To determine the nosogenetic factors of a 46,XY female with primary amenorrhea and unilateral mixed germ cell tumor. Methods Eight genes associated with 46,XY gonadal dysgenesis were detected in the patient and her parents by target region captured-next generation sequencing. Results An insertion of a single nucleotide (adenine) at the coding site 230 (c.230_231insA) located in the high mobility group (HMG) domain of SRY was revealed, which led to a truncated protein (p.Lys77fsX27). This mutation was at position 2655414 of the Y chromosome, supported with 127 unique mapped reads, however, this mutation was not found in the in-house dataset of 1 092 controls. Additionally, none of the candidate gene was detected in the patient’s parents, which indicated that it is a de novo mutation. Conclusion A novel SRY sporadic mutation due to a single nucleotide insertion at position 230 (c.230_231insA) was identified as the cause of the disease in this patient. Target region captured-next generation sequencing was found to be an effective method for the molecular genetic testing of 46,XY complete gonadal dysgenesis (46,XY CGD).