Disorders of sex development (DSD) include a heterogeneous group of heritable disorders of sex determination and differentiation. This includes chromosomal as well as monogenic disorders, which inhibit or change primarily genetic or endocrine pathways of normal sex development. However, in many patients affected, no definitive cause for the disorder can be found. Therefore, the birth of a child with ambiguous genitalia still represents an enormous challenge. For the structuring of diagnostic procedures, decision making and also therapeutic interventions, a highly specialised team of physicians of different subspecialties and experts for psychosocial care is needed to counsel parents and patients accordingly. This article presents a case with 46,XX DSD and androgen excess. After making the diagnosis on clinical and biochemical grounds, the family refused further genetic testing. The outcome of subsequent pregnancies confirmed the working diagnosis of an autosomal form of 46,XX DSD. However, the family still refused prenatal testing and treatment on religious grounds. The case discussion further illuminates the possible influence of religion in prenatal testing and concludes with the approach to the parents for comprehensive counselling in decision making for their child.
Edgar G A H van Mil and Olaf Hiort
Susanne Ledig, Olaf Hiort, Lutz Wünsch and Peter Wieacker
Ovotesticular disorder of sexual development (DSD) is an unusual form of DSD, characterized by the coexistence of testicular and ovarian tissue in the same individual. In a subset of patients, ovotesticular DSD is caused by 46,XX/46,XY chimerism or mosaicism. To date, only a few monogenetic causes are known to be associated with XX and XY ovotesticular DSD.
Design and methods
Clinical, hormonal, and histopathological data, and results of high-resolution array-comparative genomic hybridization (CGH) were obtained from a female patient with 46,XY ovotesticular DSD with testicular tissue on one side and an ovary harboring germ cells on the other. Results obtained by array-CGH were confirmed by RT-quantitative PCR.
We detected a deletion of ∼35 kb affecting exons 3 and 4 of the DMRT1 gene in a female patient with 46,XY ovotesticular DSD. To the best of our knowledge, this is the smallest deletion affecting DMRT1 presented to this point in time.
We suggest that haploinsufficiency of DMRT1 is sufficient for both XY gonadal dysgenesis and XY ovotesticular DSD. Furthermore, array-CGH is a very useful tool in the molecular diagnosis of DSD.
Susanne Thiele, Ute Hoppe, Paul-Martin Holterhus and Olaf Hiort
Objective: 5alpha-reductase enzymes reduce testosterone (T) to the most potent androgen dihydrotestosterone (DHT). Two isoenzymes are known to day. While the type 2-enzyme (5RII) is predominantly expressed in male genital tissues and mutations are known to cause a severe virilization disorder in genetic males, the role of the type 1-enzyme (5RI) in normal male androgen physiology is unclear. We investigated whether 5RI is transcribed in normal male genital skin fibroblasts (GSFs) and if the transcription is regulated by age or by androgens themselves.
Methods: GSF from 14 normally virilized males of different ages, ranging from 8 months to 72 years, obtained at circumcision were cultured. Total RNA was isolated after incubation for 48 h with 100 nM T or without androgens. Each sample was amplified in triplicate by real-time PCR with porphobilinogen desaminase as a housekeeping gene used for semiquantification. Selected cultures were analyzed after incubation with 10 and 100 nM T and 1 and 100 nM DHT for 24, 48 and 120 h.
Results: 5RI was transcribed in all investigated samples with a 4.5-fold variability in the mRNA concentration of different individuals. However, neither age-related regulation nor significant influence of T or DHT on the transcription rate was discovered.
Conclusion: Since 5RI is abundantly transcribed in GSFs, we hypothesize that this isoenzyme may play important roles in the androgen physiology of normally virilized males and may contribute to masculinization in 5RII-deficient males at the time of puberty.
Felix G Riepe, Wiebke Ahrens, Nils Krone, Regina Fölster-Holst, Jochen Brasch, Wolfgang G Sippell, Olaf Hiort and Carl-Joachim Partsch
Objective: To clarify the molecular defect for the clinical finding of congenital hypothyroidism combined with the manifestation of calcinosis cutis in infancy.
Case report: The male patient presented with moderately elevated blood thyrotropin levels at neonatal screening combined with slightly decreased plasma thyroxine and tri-iodothyronine concentrations, necessitating thyroid hormone substitution 2 weeks after birth. At the age of 7 months calcinosis cutis was seen and the patient underwent further investigation. Typical features of Albright’s hereditary osteodystrophy (AHO), including round face, obesity and delayed psychomotor development, were found.
Methods and results: Laboratory investigation revealed a resistance to parathyroid hormone (PTH) with highly elevated PTH levels and a reduction in adenylyl cyclase-stimulating protein (Gsα) activity leading to the diagnosis of pseudohypoparathyroidism type Ia (PHP Ia). A novel heterozygous mutation (c364T > G in exon 5, leading to the amino acid substitution Ile-106 → Ser) was detected in the GNAS gene of the patient. This mutation was not found in the patient’s parents, both of whom showed normal Gsα protein activity in erythrocytes and no features of AHO. A de novo mutation is therefore likely.
Conclusions: Subcutaneous calcifications in infancy should prompt the clinician to a thorough search for an underlying disease. The possibility of AHO and PHP Ia should be considered in children with hypothyroidism and calcinosis cutis. Systematic reviews regarding the frequency of calcinosis in AHO are warranted.
Birgit Köhler, Lin Lin, Inas Mazen, Cigdem Cetindag, Heike Biebermann, Ilker Akkurt, Rainer Rossi, Olaf Hiort, Annette Grüters and John C Achermann
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.
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.
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.
Friso de Vries, Mees Bruin, Angelica Cersosimo, Charlotte N van Beuzekom, S Faisal Ahmed, Robin P Peeters, Nienke R Biermasz, Olaf Hiort and Alberto M Pereira
Given that volumes of patients and interventions are important criteria to qualify as a reference centre (RC) for the European Reference Network on Rare Endocrine Conditions (Endo-ERN), the present study aimed to evaluate the data that were reported in the original application against subsequent assessments of activity and review the criteria that may define RCs using two main thematic groups (MTGs): Pituitary and Thyroid, as examples.
Review of content in application forms and continuous monitoring data and of a survey distributed to RCs. A list of ‘key procedures’ for the assessment of performance of RCs was composed with the help of the Pituitary and Thyroid MTG chairs.
In the original application, the number of undefined procedures ranged from 20 to 5500/year (Pituitary) and from 10 to 2700/year (phyroid) between applicants. In the survey, the number of key procedures per centre ranged from 18 to 150/year (Pituitary) and from 20 to 1376/year (Thyroid). The median numbers of new patients reported in the continuous monitoring program were comparable with the application and survey; however, some centres reported large variations.
Monitoring of clinical activity in an ERN requires clear definitions that are optimally aligned with clinical practice, diagnosis registration, and hospital IT systems. This is a particular challenge in the rare disease field where the centre may also provide expert input in collaboration with local hospitals. Application of uniform definitions, in addition to condition-specific clinical benchmarks, which can include patient-reported- as well as clinician-reported outcome measures, is urgently needed to allow benchmarking of care across Endo-ERN.
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.
Susanne Thiele, Giovanna Mantovani, Anne Barlier, Valentina Boldrin, Paolo Bordogna, Luisa De Sanctis, Francesca M Elli, Kathleen Freson, Intza Garin, Virginie Grybek, Patrick Hanna, Benedetta Izzi, Olaf Hiort, Beatriz Lecumberri, Arrate Pereda, Vrinda Saraff, Caroline Silve, Serap Turan, Alessia Usardi, Ralf Werner, Guiomar Perez de Nanclares and Agnès Linglart
Disorders caused by impairments in the parathyroid hormone (PTH) signalling pathway are historically classified under the term pseudohypoparathyroidism (PHP), which encompasses rare, related and highly heterogeneous diseases with demonstrated (epi)genetic causes. The actual classification is based on the presence or absence of specific clinical and biochemical signs together with an in vivo response to exogenous PTH and the results of an in vitro assay to measure Gsa protein activity. However, this classification disregards other related diseases such as acrodysostosis (ACRDYS) or progressive osseous heteroplasia (POH), as well as recent findings of clinical and genetic/epigenetic background of the different subtypes. Therefore, the EuroPHP network decided to develop a new classification that encompasses all disorders with impairments in PTH and/or PTHrP cAMP-mediated pathway.
Design and methods
Extensive review of the literature was performed. Several meetings were organised to discuss about a new, more effective and accurate way to describe disorders caused by abnormalities of the PTH/PTHrP signalling pathway.
Results and conclusions
After determining the major and minor criteria to be considered for the diagnosis of these disorders, we proposed to group them under the term ‘inactivating PTH/PTHrP signalling disorder’ (iPPSD). This terminology: (i) defines the common mechanism responsible for all diseases; (ii) does not require a confirmed genetic defect; (iii) avoids ambiguous terms like ‘pseudo’ and (iv) eliminates the clinical or molecular overlap between diseases. We believe that the use of this nomenclature and classification will facilitate the development of rationale and comprehensive international guidelines for the diagnosis and treatment of iPPSDs.