Unexpected ethical dilemmas in sex assignment in 46,XY DSD due to 5-alpha reductase type 2 deficiency

5mC modification of steroid hormone biosynthesis-related genes orchestrates feminization of channel catfish induced by high-temperature

To elucidate the mechanism behind channel catfish feminization induced by high temperature, gonad samples were collected from XY pseudo-females and wild-type females and subjected to high-throughput sequencing for Whole-Genome-Bisulfite-Seq (WGBS) and transcriptome sequencing (RNA-Seq). The analysis revealed 50 differentially methylated genes between wild-type females and XY pseudo-females, identified through the analysis of KEGG pathways and GO enrichment in the promoter of the genome and differentially methylated regions (DMRs). Among these genes, multiple differential methylation sites observed within the srd5a2 gene. Repeatability tests confirmed 7 differential methylation sites in the srd5a2 gene in XY pseudo-females compared to normal males, with 1 specific differential methylation site (16608174) distinguishing XY pseudo-females from normal females. Interestingly, the expression of these genes in the transcriptome showed no difference between wild-type females and XY pseudo-females. Our study concluded that methylation of the srd5a2 gene sequence leads to decreased expression, which inhibits testosterone synthesis while promoting the synthesis of 17β-estradiol from testosterone. This underscores the significance of the srd5a2 gene in the sexual differentiation of channel catfish, as indicated by the ipu00140 KEGG pathway analysis.

Changes in the clinical management of 5α-reductase type 2 and 17β-hydroxysteroid dehydrogenase type 3 deficiencies in France

OBJECTIVES

To examine the changes in diagnostic practices and clinical management of patients with 5α-reductase type 2 (SRD5A2) or 17β-hydroxysteroid dehydrogenase type 3 (HSD17B3) deficiency since molecular diagnoses became available.

METHODS

Clinical, laboratory, and therapeutic data were retrieved from the medical records of 52 patients with a molecular diagnosis of SRD5A2 (n = 31) or HSD17B3 (n = 21) deficiency. Temporal trends regarding age at assessment and initial sex assignment over 1994-2020 were qualitatively analyzed. Age at molecular diagnosis was compared between two subgroups of patients according to their year of birth.

RESULTS

Fifty-eight percent (n = 30) patients were diagnosed during the perinatal period, 33% (n = 17) during infancy, and 9% (n = 5) during adolescence or adulthood. Over the studied period, the patients' age at initial assessment and diagnosis frankly decreased. The median (range) age at diagnostic confirmation was 10.5 (0-53.2) years for patients born before 2007 and 0.4 (0-9.3) years for those born in 2007 or later (P = 0.029). Genetic testing identified 27 different variants for the SRD5A2 gene (30% novel, n = 8) and 18 for the HSD17B3 gene (44% novel, n = 8). Before 2002, most patients were initially assigned as females (95%, n = 19), but this proportion dropped for those born later (44%, n = 14; P < 0.001). The influence of initial genital appearance on these decisions seemingly decreased in the most recent years. Therapeutic interventions differed according to the sex of rearing. Ten percent (n = 2) patients requested female-to-male reassignment during adulthood.

CONCLUSION

This study showed, over the past two decades, a clear trend toward earlier diagnosis and assignment of affected newborns as males.

46 XY disorder of sex development (DSD) due to 5 alpha (SRD5A2) deficiency - Experience from a multidisciplinary Pediatric Gender Clinic

BACKGROUND

SRD5A2 deficiency leads to incomplete masculinization of individuals with a 46 XY karyotype. A definitive diagnosis in early infancy facilitates decisions concerning choice of sex of rearing and management.

AIM

To review the clinical presentation, diagnosis, treatment and outcome of children with 46 XY DSD due to SRD5A2 deficiency at a Paediatric Gender Clinic.

STUDY DESIGN AND METHODS

Retrospective review of cases of SRD5A2 deficiency (2000-15) managed with a standard protocol at a multidisciplinary clinic. Demographic data, clinical presentation, physical findings, investigations (hormonal profile, imaging, genitoscopy), psychological evaluation (child, family), medical and surgical management, outcome and follow up were collated and analyzed.

RESULTS

There were 12 cases aged 3 days-14 years at presentation, 3 had parental consanguinity. Eight were reared as males and 4 as females. Specialist referral was sought for hypospadias (5), atypical genitalia (5) or incongruent pubertal masculinization (2). All had chordee, symmetrical inguinoscrotal gonads, rugose labioscrotum and proximal hypospadias (perineoscrotal -9, perineal -3). Both pubertal cases had significant masculinization and no gynecomastia. The median testosterone/dihydrotestosterone ratio was 22.1(IQR-8.6-55.7). Despite a classical phenotype, four (2 prepubertal, 2 pubertal) had a ratio <10. Genitoscopy showed urogenital sinus remnant (4) and hypoplastic verumontanum (5). Sex reassignment was done in 4. Surgical management was staged and completed by 4 years in those with infantile presentation. Besides correction of chordee and urethroplasty in 11, other procedures included orchidopexy (5), excision of a urogenital sinus remnant (4) and correction of penoscrotal transposition (4). The urethroplasty was single staged in 3. All operated cases were followed up (mean age at last follow up - 10.63 years, mean follow up period - 7.25 years). The overall cosmetic result was satisfactory, but the phallic structure remained relatively small across prepubertal period. Uroflowmetry curves were normal in 9. All showed penile tumescence/erection and two peripubertal cases had typical secondary sexual characters. All cases, including those with sex reassignment, have a well-adjusted male psyche.

DISCUSSION AND CONCLUSION

The diagnosis, management and longitudinal follow up of cases of SRD5A2 deficiency at a multidisciplinary gender clinic is presented. Diagnostic dilemmas with low T/DHT ratios remained in a third of cases. Most were diagnosed in infancy and assigned a male sex of rearing, all underwent staged masculinizing genitoplasty. Those with sex reassignment also fared well with comprehensive management after family counseling.

Mutational analysis of compound heterozygous mutation p.Q6X/p.H232R in SRD5A2 causing 46,XY disorder of sex development

Background

Over 100 mutations in the SRD5A2 gene have been identified in subjects with 46,XY disorder of sex development (DSD). Exploration of SRD5A2 mutations and elucidation of the molecular mechanisms behind their effects should reveal the functions of the domains of the 5α-reductase 2 enzyme and identify the cause of 46,XY DSD. Previously, we reported a novel compound heterozygous p.Q6X/p.H232R mutation of the SRD5A2 gene in a case with 46,XY DSD. Whether the compound heterozygous p.Q6X/p.H232R mutation in this gene causes 46,XY DSD requires further exploration.

Methods

The two 46,XY DSD cases were identified and sequenced. In order to identify the source of the compound heterozygous p.Q6X/p.H232R mutation, the parents, maternal grandparents, and maternal uncle were sequenced. Since p.Q6X mutation is a nonsense mutation, p.H232R mutation was transfected into HEK293 cells and dihydrotestosterone (DHT) production were analyzed by liquid chromatography–mass spectrometry (LC–MS) for 5α-reductase 2 enzyme activities test. Apparent michaelis constant (Km) were measured of p.H232R mutation to analyze the binding ability change of 5α-reductase 2 enzyme with testosterone (T) or NADPH.

Results

The sequence results showed that the two 46,XY DSD cases were the compound heterozygous p.Q6X/p.H232R mutation, of which the heterozygous p.Q6X mutation originating from maternal family and heterozygous p.H232R mutation originating from the paternal family. The function analysis confirmed that p.H232R variant decreased the DHT production by LC–MS test. The Km analysis demonstrated that p.H232R mutation affected the binding of SRD5A2 with T or NADPH.

Conclusions

Our findings confirmed that the compound heterozygous p.Q6X/p.H232R mutation in the SRD5A2 gene is the cause of 46,XY DSD. p.H232R mutation reduced DHT production while attenuating the catalytic efficiency of the 5α-reductase 2 enzyme.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13052-022-01243-4.

Novel Deleterious Mutation in Steroid-5α-Reductase-2 in 46, XY Disorders of Sex Development: Case Report Study

Background: Steroid-5α-reductase-2 (SRD5A2) and 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) enzyme deficiencies are frequent causes of 46, XY disorder of sex development (46, XY DSD), where an infant with 46, XY has a female phenotype. We assessed the hydroxy-steroid-17β-dehydrogenase-3 (HSD17B3)and SRD5A2 genes in twenty Iranian phenotypic females with 46,XY DSD. Materials and methods: All exons in HSD17B3 and SRD5A2 genes were subjected to PCR amplification followed by sequencing. Results: Of 20 identified 46, XY DSD patients, one had a homozygous missense 17β-HSD3 mutation Ser65Leu (c.194C > T). We found 1 SRD5A2 novel homozygous missense mutation of Tyr242Asp (c.891T > G) in exon 5, which in-silico analyses revealed that this mutation may have deleterious impact on ligand binding site of SRD5A2 protein. Three other individuals harbored 17β-HSD3 deficiencies without identified mutations. Conclusions: SRD5A2 and 17β-HSD3 mutations are found in 10% of 46, XY DSD Iranian patients.

Primary Amenorrhea Due to Anatomical Abnormalities of the Reproductive Tract: Molecular Insight

Congenital anomalies of the female reproductive tract that present with primary amenorrhea involve Müllerian aplasia, also known as Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS), and cervical and vaginal anomalies that completely obstruct the reproductive tract. Karyotype abnormalities do not exclude the diagnosis of MRKHS. Familial cases of Müllerian anomalies and associated malformations of the urinary and skeletal systems strongly suggest a complex genetic etiology, but so far, the molecular mechanism in the vast majority of cases remains unknown. Primary amenorrhea may also be the first presentation of complete androgen insensitivity syndrome, steroid 5α-reductase type 2 deficiency, 17β-hydroxysteroid dehydrogenase type 3 deficiency, and Leydig cells hypoplasia type 1; therefore, these disorders should be considered in the differential diagnosis of the congenital absence of the uterus and vagina. The molecular diagnosis in the majority of these cases can be established.

Exome sequencing identified compound heterozygous mutations in the SRD5A2 gene in a case of 46,XY ambiguous genitalia

The disorders of sexual development (DSD) represent an array of phenotypes with ambiguous genitalia. The present case had microphallus with fused and bifid scrotum and was initially assigned androgen insensitivity syndrome; however, sequencing of the complete coding region of the androgen receptor gene failed to identify a causative mutation. We undertook whole exome sequencing for identification of the pathogenic mutation. The most promising pathogenic variants were genotyped using Sanger sequencing to confirm the genotypes. We found compound heterozygous mutations, c.169G>T and c.586G>A in the SRD5A2 gene in this case, resulting in a nonsense (p.Glu57Ter) and a nonsynonymous substitution (p.Gly196Ser), respectively. While the nonsense mutation would result in a truncated protein, p.Gly196Ser substitution has been previously reported to be pathogenic. The mutations were confirmed by Sanger sequencing. Sequencing of 96 normal male individuals did not show the above mutations, suggesting their pathogenic nature. In conclusion, we identified compound heterozygous pathogenic mutations, c.169G>T (p.Glu57Ter) and c.586G>A (p.Gly196Ser), in the SRD5A2 gene in a case of ambiguous genitalia. p.Glu57Ter is a novel mutation, which in compound heterozygote combination with Gly196Ser causes 5a reductase deficiency.

Individualized care for patients with intersex (disorders/differences of sex development): Part 3

The focus of this article is to review the complex determinants of gender assignment in a child with a disorder of sex development using four different clinical cases. While the care of patients with DSD may be shared across several specialties and opinions regarding their management may vary, this may be further complicated by psychosocial, cultural and economic factors. In this regard, access to behavioral health specialists with experience and specialization in the treatment of patients with DSD should be a foundational component of the standard of care and can greatly assist in the complex decision-making regarding gender assignment. We recommend an individualized approach by a multidisciplinary team utilizing a range of evolving strategies, including outcome data (or lack thereof) to support families during the decision-making process.

A non-surgical approach to 46,XY differences in sex development through hormonal suppression at puberty: a single-center case series study

PURPOSE

We aim to report outcomes and safety with hormonal suppression to facilitate gonadal preservation in a select group of patients with 46,XY differences in sex development (DSD) who are raised and identify as female yet have diagnoses with potential for androgenization at puberty.

METHODS

We performed a retrospective review of the past 10 years of DSD patients treated by a multidisciplinary program. Inclusion criteria were 46,XY DSD, female sex of rearing, risk of androgenization at puberty, and plan for hormonal suppression at puberty. Patients on hormonal suppression had at least 6 months of follow-up from initiation. We excluded those with complete gonadal dysgenesis or complete androgen insensitivity.

RESULTS

Four patients met inclusion criteria. Initial evaluation by DSD team was at a mean age of 6.6 years (3 weeks-16 years). All patients were evaluated in a coordinated multidisciplinary clinic. The diagnoses are listed in Table 1. Mean follow-up was 5.7 years (1.2-10.9 years). One patient presented as an infant, and is being monitored until Tanner stage 2 and/or serum hormonal evidence to initiate hormonal suppression. Three patients have been receiving hormonal suppression for 1.4 years (1.1-1.9 years) without side effects or complication. Three patients were initiated with estrogen replacement to promote desired breast development. At last follow-up, all patients had retained their gonads, all have female gender identity with no reported gender dysphoria, and no progression of androgenization.

CONCLUSIONS

In our initial experience, gonadal preservation with hormonal suppression is a tool in multidisciplinary management of select DSD patients with female gender identity with conditions associated with androgenization at puberty. Patients' growth, bone health, and overall psychosocial well-being will need to be monitored closely.

5α-Reductase-2 deficiency: is gender assignment recommended in infancy? Two case-reports and review of the literature

PURPOSE

Gender assignment represents one of the most controversial aspects of the clinical management of individuals with Differences of Sex Development, including 5α-Reductase-2 deficiency (SRD5A2). Given the predominant female appearance of external genitalia in individuals with SRD5A2 deficiency, most of them were assigned to the female sex at birth. However, in the last years the high rate of gender role shift from female to male led to recommend a male gender assignment.

METHODS

We here describe two cases of subjects with SRD5A2 deficiency assigned as females at birth, reporting their clinical histories and psychometric evaluations (Body Uneasiness Test, Utrecht Gender Dysphoria Scale, Bem Sex-Role Inventory, Female Sexual Distress Scale Revised, visual analogue scale for gender identity and sexual orientation) performed at the time of referral at the Florence Gender Clinic.

RESULTS

Both patients underwent early surgical interventions without being included in the decision-making process. They had to conform to a binary feminine gender role because of social/familiar pressure, with a significant impact on their psychological well-being. Psychometric evaluations identified clinically significant body uneasiness and gender incongruence in both subjects. No sexually related distress and undifferentiated gender role resulted in the first subject and sexually related distress and androgynous gender role resulted in the second subject.

CONCLUSIONS

The reported cases suggest the possibility to consider a new approach for gender assignment in these individuals, involving them directly in the decision-making process and allowing them to explore their gender identity, also with the help of GnRH analogues to delay pubertal modifications.

Novel Genotype in Two Siblings with 5-α-reductase 2 Deficiency: Different Clinical Course due to the Time of Diagnosis

Steroid 5-α-reductase-2 (5-ARD) deficiency is a result of mutations of the SRD5A2 gene. It causes the disorder of sexual differentiation (DSD) in 46,XY individuals with a variable genital phenotype. We present two siblings with female external genitalia at birth and bilateral inguinal testes, raised as females. These are the first molecularly characterized patients from the Republic of North Macedonia (RN Macedonia) with a different clinical course due to the time of the diagnosis. Diagnosis of Patient 1 was based upon the detection of bilateral inguinal testes and testosterone/dihidrotestosterone ratio. Sex reversal was initiated by testes removal at the age of 20 months. Breast implantation and vaginoplasty were performed in adolescence and the girl is comfortable with the female sex. Her sibling, Patient 2, raised as a girl, was clinically assessed at 11.5 years due to the growth of phalus, deep voice and Adam's apple enlargement. No change of gender was accepted. Complex molecular analysis including multiplex quantitative fluorescent polymerase chain reaction (PCR) screening for sex chromosome aneuploidies and SRY presence, Sanger sequencing combined with multiplex ligation-dependent probe amplification (MLPA), microarray-based comparative genomic hybridization (aCGH), and real-time PCR analysis for detection of exon copy number changes confirmed a novel c.146C>A (p.Ala49Asp) point mutation in the first exon inherited from the mother, and complete deletion of the first exon and adjacent regions inherited from the father. Novel genotype causing 5-ARD is presented. Genetic analysis is useful for the diagnosis and timely gender assignment in patients with 5-ARD. However, final gender assignment is difficult and requires combined medical interventions.

Growth Pattern in Chinese Children With 5α-Reductase Type 2 Deficiency: A Retrospective Multicenter Study

BACKGROUND

5α-reductase type 2 deficiency (5αRD) is an autosomal recessive hereditary disease of the group of 46, XY disorders of sex development (DSD).

OBJECTIVE

To study the growth pattern in Chinese pediatric patients with 5αRD.

SUBJECTS

Data were obtained from 141 patients with 5αRD (age: 0-16 years old) who visited eight pediatric endocrine centers from January 2010 to December 2017.

METHODS

In this retrospective cohort study, height, weight, and other relevant data were collected from the multicenter hospital registration database. Baseline luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T), and dihydrotestosterone (DHT) after human chorionic gonadotropin (HCG) stimulation test were measured by enzyme enhanced chemiluminescence assay. Bone age (BA) was assessed using the Greulich-Pyle (G-P) atlas. Growth curve was constructed based on λ-median-coefficient of variation method (LMS).

RESULTS

The height standard deviation scores (HtSDS) and weight standard deviation scores (WtSDS) in 5αRD children were in the normal range as compared to normal boys. Significantly higher HtSDS was observed in patients with 5αRD who were <1 year old (t = 3.658, 2.103, P = 0.002, 0.048, respectively), and higher WtSDS in those <6 months old (t = 2.756, P = 0.012). Then HtSDS and WtSDS decreased gradually and fluctuated near the median of the same age until 13 years. WtSDS in 5αRD children from northern China were significantly higher than those from the south (Z = -2.670, P = 0.008). The variation tendency of HtSDS in Chinese 5αRDs was consistent with the trend of stimulating T. HtSDS and stimulating T in the external masculinization score (EMS) <7 group were slightly higher than those in EMS ≥ 7 group without significant difference. Additionally, the ratio of BA over chronological age (BA/CA) was significantly <1 in children with 5αRD.

CONCLUSION

Children with 5αRD had a special growth pattern that was affected by high levels of T, while DHT played a very small role in it. Their growth accelerated at age <1 year, followed by slowing growth and fluctuating height near normal median boys' height. The BA was delayed in 5αRD children. Androgen treatment, which may be considered anyway for male 5αRD patients with a micropenis, may also be beneficial for growth.

Sex assignment practice in disorders of sexual differentiation: survey results from paediatric endocrinologists in the Arab region

Background Sex assignment is a major issue in disorders of sexual differentiation (DSD). Not all conditions of DSD have clear recommendations on assignment and timing of surgery. Reports about sex assignment practice and the influence of culture and religion in the Arab region are scarce. Methods A survey questionnaire was distributed to participants in a paediatric endocrinology conference. Four DSD cases were presented. Participants were asked to fill in their answers on sex assignment choice, reasons for the particular assignment, strength of own recommendation and timing of surgery based on their practice. The cases presented were severely virilised XX congenital adrenal hyperplasia (CAH), complete androgen insensitivity syndrome (CAIS), severely undervirilised 5α reductase deficiency (5α RD) and XX ovotesticular case. Results Eighty-five endocrinologists participated in the study. Eighty (97.5%) chose a female sex to assign for the XX CAH. For the CAIS, 64 (78%) chose a female sex. Seventy-one (86.5%) voted for a male sex for the XY case of 5α RD. Forty-seven (57%) and 35 (43%) chose a female and a male sex for the ovotesticular case, respectively. The majority indicated that their advice for sex assignment is based on strong recommendations for the CAH, CAIS and 5α RD patients but they were open to the parents' cultural and religious beliefs in their decision of the assignment for the ovotesticular case. Conclusions Practice in the Arab region appears to be in line with the international guidelines in the majority of DSD sex assignment and timing of surgery issues. However, culture and religious beliefs influence the practice in certain circumstances.