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Open access

Sally Tantawy, Lin Lin, Ilker Akkurt, Guntram Borck, Dietrich Klingmüller, Berthold P Hauffa, Heiko Krude, Heike Biebermann, John C Achermann and Birgit Köhler

Background

Steroidogenic factor 1 (SF-1, NR5A1) is a key transcriptional regulator of many genes involved in the hypothalamic–pituitary–gonadal axis and mutations in NR5A1 can result in 46,XY disorders of sex development (DSD). Patients with this condition typically present with ambiguous genitalia, partial gonadal dysgenesis, and absent/rudimentary Müllerian structures. In these cases, testosterone is usually low in early infancy, indicating significantly impaired androgen synthesis. Further, Sertoli cell dysfunction is seen (low inhibin B, anti-Müllerian hormone). However, gonadal function at puberty in patients with NR5A1 mutations is unknown.

Subjects and methods

Clinical assessment, endocrine evaluation, and genetic analysis were performed in one female and one male with 46,XY DSD who showed spontaneous virilization during puberty. The female patient presented at adolescence with clitoral hypertrophy, whereas the male patient presented at birth with severe hypospadias and entered puberty spontaneously. Molecular analysis of NR5A1 was performed followed by in vitro functional analysis of the two novel mutations detected.

Results

Testosterone levels were normal during puberty in both patients. Analysis of NR5A1 revealed two novel heterozygous missense mutations in the ligand-binding domain of SF-1 (patient 1: p.L376F; patient 2: p.G328V). The mutant proteins showed reduced transactivation of the CYP11A promoter in vitro.

Conclusion

Patients with 46,XY DSD and NR5A1 mutations can produce sufficient testosterone for spontaneous virilization during puberty. Phenotypic females (46,XY) with NR5A1 mutations can present with clitoromegaly at puberty, a phenotype similar to other partial defects of androgen synthesis or action. Testosterone production in 46,XY males with NR5A1 mutations can be sufficient for virilization at puberty. As progressive gonadal dysgenesis is likely, gonadal function should be monitored in adolescence and adulthood, and early sperm cryopreservation considered in male patients if possible.

Open access

Birgit Köhler, Lin Lin, Inas Mazen, Cigdem Cetindag, Heike Biebermann, Ilker Akkurt, Rainer Rossi, Olaf Hiort, Annette Grüters and John C Achermann

Objective

Hypospadias is a frequent congenital anomaly but in most cases an underlying cause is not found. Steroidogenic factor 1 (SF-1, NR5A1, Ad4BP) is a key regulator of human sex development and an increasing number of SF-1 (NR5A1) mutations are reported in 46,XY disorders of sex development (DSD). We hypothesized that NR5A1 mutations could be identified in boys with hypospadias.

Design and methods

Mutational analysis of NR5A1 in 60 individuals with varying degrees of hypospadias from the German DSD network.

Results

Heterozygous NR5A1 mutations were found in three out of 60 cases. These three individuals represented the most severe end of the spectrum studied as they presented with penoscrotal hypospadias, variable androgenization of the phallus and undescended testes (three out of 20 cases (15%) with this phenotype). Testosterone was low in all three patients and inhibin B/anti-Müllerian hormone (AMH) were low in two patients. Two patients had a clear male gender assignment. Gender re-assignment to male occurred in the third case. Two patients harbored heterozygous nonsense mutations (p.Q107X/WT, p.E11X/WT). One patient had a heterozygous splice site mutation in intron 2 (c.103-3A/WT) predicted to disrupt the main DNA-binding motif. Functional studies of the nonsense mutants showed impaired transcriptional activation of an SF-1-responsive promoter (Cyp11a). To date, adrenal insufficiency has not occurred in any of the patients.

Conclusions

SF-1 (NR5A1) mutations should be considered in 46,XY individuals with severe (penoscrotal) hypospadias, especially if undescended testes, low testosterone, or low inhibin B/AMH levels are present. SF-1 mutations in milder forms of idiopathic hypospadias are unlikely to be common.

Free access

Sally Tantawy, Inas Mazen, Hala Soliman, Ghada Anwar, Abeer Atef, Mona El-Gammal, Ahmed El-Kotoury, Mona Mekkawy, Ahmad Torky, Agnes Rudolf, Pamela Schrumpf, Annette Grüters, Heiko Krude, Marie-Charlotte Dumargne, Rebekka Astudillo, Anu Bashamboo, Heike Biebermann and Birgit Köhler

Objective

Steroidogenic factor 1 (SF1, NR5A1) is a key transcriptional regulator of genes involved in the hypothalamic–pituitary–gonadal axis. Recently, SF1 mutations were found to be a frequent cause of 46,XY disorders of sex development (DSD) in humans. We investigate the frequency of NR5A1 mutations in an Egyptian cohort of XY DSD.

Design

Clinical assessment, endocrine evaluation and genetic analysis of 50 Egyptian XY DSD patients (without adrenal insufficiency) with a wide phenotypic spectrum.

Methods

Molecular analysis of NR5A1 gene by direct sequencing followed by in vitro functional analysis of the two novel missense mutations detected.

Results

Three novel heterozygous mutations of the coding region in patients with hypospadias were detected. p.Glu121AlafsX25 results in severely truncated protein, p.Arg62Cys lies in DNA-binding zinc finger, whereas p.Ala154Thr lies in the hinge region of SF1 protein. Transactivation assays using reporter constructs carrying promoters of anti-Müllerian hormone (AMH), CYP11A1 and TESCO core enhancer of Sox9 showed that p.Ala154Thr and p.Arg62Cys mutations result in aberrant biological activity of NR5A1. A total of 17 patients (34%) harboured the p.Gly146Ala polymorphism.

Conclusion

We identified two novel NR5A1 mutations showing impaired function in 23 Egyptian XY DSD patients with hypospadias (8.5%). This is the first study searching for NR5A1 mutations in oriental patients from the Middle East and Arab region with XY DSD and no adrenal insufficiency, revealing a frequency similar to that in European patients (6.5–15%). We recommend screening of NR5A1 in patients with hypospadias and gonadal dysgenesis. Yearly follow-ups of gonadal function and early cryoconservation of sperms should be performed in XY DSD patients with NR5A1 mutations given the risk of future fertility problems due to early gonadal failure.

Restricted access

Christa Flück, Anna Nordenström, S Faisal Ahmed, Salma R Ali, Marta Berra, Joanne Hall, Birgit Köhler, Vickie Pasterski, Ralitsa Robeva, Katinka Schweizer, Alexander Springer, Puck Westerveld, Olaf Hiort, Martine Cools and the COST Action BM1303 Working Group

The treatment and care of individuals who have a difference of sex development (DSD) have been revised over the past two decades and new guidelines have been published. In order to study the impact of treatments and new forms of management in these rare and heterogeneous conditions, standardised assessment procedures across centres are needed. Diagnostic work-up and detailed genital phenotyping are crucial at first assessment. DSDs may affect general health, have associated features or lead to comorbidities which may only be observed through lifelong follow-up. The impact of medical treatments and surgical (non-) interventions warrants special attention in the context of critical review of current and future care. It is equally important to explore gender development early and refer to specialised services if needed. DSDs and the medical, psychological, cultural and familial ways of dealing with it may affect self-perception, self-esteem, and psychosexual function. Therefore, psychosocial support has become one of the cornerstones in the multidisciplinary management of DSD, but its impact remains to be assessed. Careful clinical evaluation and pooled data reporting in a global DSD registry will allow linking genetic, metabolomic, phenotypic and psychological data. For this purpose, our group of clinical experts and patient and parent representatives designed a template for structured longitudinal follow-up. In this paper, we explain the rationale behind the selection of the dataset. This tool provides guidance to professionals caring for individuals with a DSD and their families. At the same time, it collects the data needed for answering unsolved questions of patients, clinicians, and researchers. Ultimately, outcomes for defined subgroups of rare DSD conditions should be studied through large collaborative endeavours using a common protocol.