NR5A1 Mutations Research Articles

Next generation sequencing (NGS) to improve the diagnosis and management of patients with disorders of sex development (DSD).

Disorders of sex development (DSDs) are a diverse group of conditions where the chromosomal, gonadal or anatomical sex can be atypical. The highly heterogeneous nature of this group of conditions often makes determining a genetic diagnosis challenging. Prior to next generation sequencing (NGS) technologies, genetic diagnostic tests were only available for a few of the many DSD-associated genes, which consequently had to be tested sequentially. Genetic testing is key in establishing the diagnosis, allowing for personalised management of these patients. Pinpointing the molecular cause of a patient’s DSD can significantly impact patient management by informing future development needs, altering management strategies and identifying correct inheritance pattern when counselling family members. We have developed a 30-gene NGS panel, designed to be used as a frontline test for all suspected cases of DSD (both 46,XX and 46,XY cases). We have confirmed a diagnosis in 25 of the 80 patients tested to date. Confirmed diagnoses were linked to mutations in AMH, AMHR2, AR, HSD17B3, HSD3B2, MAMLD1, NR5A1, SRD5A2 and WT1 which have resulted in changes to patient management. The minimum diagnostic yield for patients with 46,XY DSD is 25/73. In 34/80 patients, only benign or likely benign variants were identified, and in 21/80 patients only variants of uncertain significance (VOUS) were identified, resulting in a diagnosis not being confirmed in these individuals. Our data support previous studies that an NGS panel approach is a clinically useful and cost-effective frontline test for patients with DSDs.

Phenotype and Molecular Characterizations of 30 Children From China With NR5A1 Mutations.

Background: Patients harboring NR5A1 mutations have a wide spectrum of phenotypes.Objective: To investigate the phenotype of patients with NR5A1 gene mutations from a 30 Chinese patient cohort.Methods: We reported the clinical features of children with NR5A1 gene mutations and compared them between two groups of patients with social genders of male (boys group) and female (girls group).Results: Thirty patients with NR5A1 mutations ranging from 2 months to 17 years of age were studied. There were 11 boys and 19 girls who were identified when they visited the hospital. The patients were verified as having testes without a uterus and ovaries by B-mode ultrasound. There was no difference between boys and girls in terms of the Prader stage (p = 0.086), but the position of the testes was higher in girls than in boys (p = 0.013). The patients’ average height is −0.43 SDS according to the normal boys’ height with SDS (while their average target height was 0.07 SDS). However, there was no such difference between boys and girls (p > 0.05). Although the basal LH and post-hCG testosterone (T) levels were not different (p > 0.05), but the basal FSH level, LH/FSH ratio, and INHB level were decreased in girls (p = 0.002; p = 0.001; p = 0.006). All of the mothers of the patients reported to have normal pregnancies. We found 24 patients (80%) with de novo mutations in the NR5A1 gene; 5 patients had inherited mutations from their mothers, and one inherited from the father. Only the mothers of patients 16 and 18 showed premature ovarian failure at the time of reporting. Among 26 disease associated mutations, 14 novel mutations that have been reported the first time and p.R87C is the most common Among the other 12 had had been reported,the p.R313C is the most common.Conclusion: Patients with 46, XY NR5A1 mutations presented a wide spectrum of external genitalia characteristics and severe Sertoli cell impairment. The p.R87C and p.R313C mutations appeared to be common (10%) in this group, and 14 new mutations were identified, improving our understanding the genotype phenotype correlations.

Novel NR5A1 mutations found in Chinese patients with 46, XY disorders of sex development.

To analyze nuclear receptor subfamily 5 group A member 1 (NR5A1) gene mutations in a cohort of Chinese patients with 46, XY Disorders of Sex Development (DSD). Sixty 46, XY DSD patients were recruited at Peking Union Medical College Hospital. Targeted next-generation and Sanger sequencing were performed to investigate pathogenic gene variants and validate NR5A1 gene variants, respectively. In silico tools and in vitro function studies were used to analyze the pathogenicity of rare variants. The clinical and endocrinological characteristics of patients with NR5A1 variants were retrospectively analyzed. A total of four novel and three recurrent NR5A1 variants were identified in seven 46, XY DSD patients. These variants widely spread almost all the functional domains. Functional studies showed that novel mutations including p.S32N, p.N44del and p.G91D reduced transactivation of CYP11A1, while the other missense variant p.A168E did not impact protein function. All patients with NR5A1 rare variants had normal adrenal function and showed genital defects. Results of the genitalia examination showed female external genitalia (three patients), ambiguous external genitalia (two patients), female external genitalia with clitoromegaly (one patient), and hypospadias (one patient). All seven patients had bilateral testis and five of seven patients lacked Müllerian structures. Four novel mutations in the NR5A1 gene were identified in our cohort with 46, XY DSD, expanding the spectrum of NR5A1 gene mutations. All patients with NR5A1 rare variants had normal adrenal function and showed genital defects.

Next-generation sequencing reveals genetic landscape in 46, XY disorders of sexual development patients with variable phenotypes

Disorders of sexual development (DSD) are rare congenital conditions in which chromosomal, gonadal, or anatomical sex is atypical. Currently, less than 20% of patients receive an accurate genetic diagnosis. Targeted next-generation sequencing, consisting of 33 candidate genes and 47 genes involved in sexual differentiation and development, was performed on 70 46, XY DSD patients. Functional assays were performed to evaluate the expression and transcriptional activity of one reported and nine novel mutations of NR5A1. In total, 113 mutations, including 86 novel and 27 reported sites in 40 genes, were identified in 52 patients. Among them, 37 mutations from 19 genes were first identified in 46, XY DSD patients, including EGF, LHX9, and CST9. Nine patients displayed biallelic mutations, 12 had mutations in sex chromosome genes and 14 had monoallelic mutations in NR5A1, BMP4, and WT1. Higher frequency mutations were identified in AR, SRD5A2, and NR5A1. Six missense, one frameshift, and one three-nucleotide deletion mutations of NR5A1 were shown to impair the transactivation ability with an altered nuclear aggregation of p.T29K and p.N44del variants. Multiple genetic mutations were identified in 33 of the 70 patients. The targeted sequencing panel provides an efficient method for the etiological diagnosis of 46, XY DSD patients and expands the candidate genes and inherited patterns.

The wide clinical expression spectrum presented in two families with NR5A1 mutation

Context: Patients with NR5A1 mutations present a wide spectrum of phenotype. The gene is frequently associated with 46, XY disorders of sex development (DSD). Objectives: To analyze the clinical expression and NR5A1 mutations in two families with probands presenting 46, XY DSD. Results: Two probands with 46, XY gonadal dysgenesis from two unconsanguineous families showed spontaneous puberty, normal levels of ACTH, cortisol, testosterone, increased FSH and decreased LH/FSH, AMH and INHB. In Family 1, a novel pathogenic variant, p.C33X, was identified in the proband. By determining other members in this family, the variant was found in the proband’s mother, two elder sisters and two nephews. However, no obvious anomaly was presented in the eldest sister with the variant while her two sons showed hypospadias. In Family 2, the proband inherited a reported pathogenic variant, p.M1I from his mother who delivered 4 children by natural pregnancy. The self-reported family puberty and fertility history was negative until we calculated the exact menopause age of mothers at 36 and 41 years of age respectively. Conclusion: The 46, XY DSD patients with NR5A1variants show highly variable phenotypes, from complete female genitalia to ambiguous external genitals/hypospadias. While 46, XX individual may have inconspicuous symptoms. Normal fertility is not a reliable negative family history on this disease. The identified novel pathogenic variant, p.C33X in patient 46, XY DSD and 46, XX primary ovarian insufficiency extends the genotypic and phenotypic spectrum of NR5A1. This study also highlights the critical role of NR5A1 protein in gonadal development and differentiation.

NR5A1 mutations are not associated with male infertility in Indian men.

NR5A1 or steroidogenic factor 1 (SF1) is an autosomal gene, which encodes a protein that is a member of nuclear receptor family. NR5A1 regulates the transcription of numerous genes that are expressed in hypothalamic-pituitary-gonadal axis and adrenal cortex which in turn, coordinate the gonadal development, steroidogenesis and sex differentiation. Several mutations in NR5A1 have been reported to cause gonadal dysgenesis with adrenal insufficiency in individuals with 46,XY karyotype. However, studies in the past few years have shown that NR5A1 mutations can also contribute to primary ovarian insufficiency and impaired spermatogenesis. As there is no genetic study on NR5A1 in Indian infertile men, we have sequenced the entire coding region (exons 2-7) of NR5A1 in 502 infertile men of which, 414 were non-obstructive azoospermic and 88 severe oligozoospermic, along with 427 ethnically matched fertile controls. Interestingly, none of the mutations reported to be associated with male infertility were found in our study, except one polymorphism, rs1110061. However, it was not significantly different between infertile and fertile groups (p=.76). In addition, we have identified six intronic variants; but none of them was significantly associated with male infertility.

Four Novel NR5A1 Mutations in 46,XY Gonadal Dysgenesis Patients Including Frameshift Mutations with Altered Subcellular SF-1 Localization

46,XY gonadal dysgenesis (46,XY GD) is a disorder of sexual development caused by mutations in genes involved in early gonadal development (bipotential gonads) and testis differentiation. In 46,XY GD individuals, mutations of the SRY gene are detected most frequently, followed by mutations in the NR5A1 (SF-1) gene, but in a lot of cases, the underlying molecular mechanism remains elusive. In this study, we retrospectively performed sequence analyses of the NR5A1 (SF-1) gene in 84 patients with complete, partial, and syndromic forms of 46,XY GD. In total, 7 heterozygous mutations were found in 6 of 84 patients (7.1%). Among these, we identified 4 mutations that, to the best of our knowledge, have not been reported before (c.268G>T, c.369del, c.871-1G>C, and c.893T>C). Transfection of different mutations revealed altered subcellular localization of the mutant SF-1 protein in the case of the frameshift mutations, indicating an impaired protein function. In conclusion, we present 4 novel mutations of the NR5A1 gene associated with 46,XY GD together with in vitro data pointing towards a possible functional impairment of the mutant SF-1 proteins.

A novel C-terminal truncating NR5A1 mutation in dizygotic twins

Nuclear receptor subfamily 5, group A, member 1 (NR5A1) is a nuclear receptor involved in gonadal and adrenal development. We identified a novel C-terminally truncating NR5A1 mutation, p.Leu423Trpfs*7, in dizygotic twins with 46,XY disorders of sex development. Our results highlight the functional importance of C-terminal region of NR5A1 and indicate that NR5A1 mutations can be associated with intrafamilial phenotypic variations, progressive testicular dysfunction, hypogonadotropic hypogonadism, and borderline adrenal dysfunction.

Recent findings on the genetics of disorders of sex development.

Disorders of sex development (DSD) are a diverse group of conditions affecting gonadal development, sexual differentiation, or chromosomal sex. In this review, we will discuss recent literature on the genetic causes of DSD, with a focus on novel genetic sequencing technologies, new phenotypes associated with known DSD genes, and increasing recognition of the role of genetic regulatory elements in DSD. We performed a comprehensive search of PubMed through August 2016 to identify important peer-reviewed publications from 2015 to 2016 on the topic of DSD genetics. Whole-exome sequencing was used to successfully identify genetic causes of DSD in 35% of a cohort of 46,XY patients who had not previously received a genetic diagnosis. A novel mutation in NR5A1 has been identified as a cause of 46,XX testicular and ovotesticular DSD, demonstrating a previously unappreciated role of NR5A1 in preventing testicular differentiation in 46,XX individuals. Genetic regulatory elements of SOX9 have been identified as causes of 46,XX and 46,XY DSD.

Wide spectrum of NR5A1-related phenotypes in 46,XY and 46,XX individuals.

Steroidogenic factor 1 (NR5A1, SF‐1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1‐related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype‐phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian‐determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1‐related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever‐expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal dysfunction. Birth Defects Research (Part C) 108:309–320, 2016. © 2016 The Authors Birth Defects Research Part C: Embryo Today: Reviews Published by Wiley Periodicals, Inc.

A recurrent p.Arg92Trp variant in steroidogenic factor-1 (NR5A1) can act as a molecular switch in human sex development.

Cell lineages of the early human gonad commit to one of the two mutually antagonistic organogenetic fates, the testis or the ovary. Some individuals with a 46,XX karyotype develop testes or ovotestes (testicular or ovotesticular disorder of sex development; TDSD/OTDSD), due to the presence of the testis-determining gene, SRY Other rare complex syndromic forms of TDSD/OTDSD are associated with mutations in pro-ovarian genes that repress testis development (e.g. WNT4); however, the genetic cause of the more common non-syndromic forms is unknown. Steroidogenic factor-1 (known as NR5A1) is a key regulator of reproductive development and function. Loss-of-function changes in NR5A1 in 46,XY individuals are associated with a spectrum of phenotypes in humans ranging from a lack of testis formation to male infertility. Mutations in NR5A1 in 46,XX women are associated with primary ovarian insufficiency, which includes a lack of ovary formation, primary and secondary amenorrhoea as well as early menopause. Here, we show that a specific recurrent heterozygous missense mutation (p.Arg92Trp) in the accessory DNA-binding region of NR5A1 is associated with variable degree of testis development in 46,XX children and adults from four unrelated families. Remarkably, in one family a sibling raised as a girl and carrying this NR5A1 mutation was found to have a 46,XY karyotype with partial testicular dysgenesis. These unique findings highlight how a specific variant in a developmental transcription factor can switch organ fate from the ovary to testis in mammals and represents the first missense mutation causing isolated, non-syndromic 46,XX testicular/ovotesticular DSD in humans.

NR5A1 is a novel disease gene for 46,XX testicular and ovotesticular disorders of sex development

Purpose:We aimed to identify the genetic cause in a cohort of 11 unrelated cases and two sisters with 46,XX SRY-negative (ovo)testicular disorders of sex development (DSD).Methods:Whole-exome sequencing (n = 9), targeted resequencing (n = 4), and haplotyping were performed. Immunohistochemistry of sex-specific markers was performed on patients’ gonads. The consequences of mutation were investigated using luciferase assays, localization studies, and RNA-seq.Results:We identified a novel heterozygous NR5A1 mutation, c.274C>T p.(Arg92Trp), in three unrelated patients. The Arg92 residue is highly conserved and located in the Ftz-F1 region, probably involved in DNA-binding specificity and stability. There were no consistent changes in transcriptional activation or subcellular localization. Transcriptomics in patient-derived lymphocytes showed upregulation of MAMLD1, a direct NR5A1 target previously associated with 46,XY DSD. In gonads of affected individuals, ovarian FOXL2 and testicular SRY-independent SOX9 expression observed.Conclusions:We propose NR5A1, previously associated with 46,XY DSD and 46,XX primary ovarian insufficiency, as a novel gene for 46,XX (ovo)testicular DSD. We hypothesize that p.(Arg92Trp) results in decreased inhibition of the male developmental pathway through downregulation of female antitestis genes, thereby tipping the balance toward testicular differentiation in 46,XX individuals. In conclusion, our study supports a role for NR5A1 in testis differentiation in the XX gonad.Genet Med19 4, 367–376.

NR5A1 Loss-of-Function Mutations Lead to 46,XY Partial Gonadal Dysgenesis Phenotype: Report of Three Novel Mutations

Mutations in the NR5A1 gene, which encodes the steroidogenic factor 1 (SF1), are responsible for different phenotypes of disorders of sex development (DSD), such as bilateral anorchia and hypospadias. Furthermore, they can be associated with primary amenorrhea, premature ovarian failure, male infertility, adrenal tumors, and endometriosis. Direct sequencing of the 7 NR5A1 exons including ∼1,000 bp of the 5′-upstream and 3′-downstream regions and all intron-exon boundaries was performed in patients with DSD. Three different in silico tools were used to assess the consequences of a splice site mutation. As a result, 3 novel NR5A1 mutations were identified in 3 patients with 46,XY partial gonadal dysgenesis: p.Lys38* and p.Leu80Trpfs*8 lead to premature translation termination codons within the SF1 DNA-binding domain, and the intronic nucleotide substitution c.1138+1G>T at the intron 6 donor splice site is considered to modify correct splicing. We assume that the anomalous mRNA produced as a result of p.Lys38* and p.Leu80Trpfs*8 will be degraded by nonsense-mediated mRNA decay even before translation, leading to SF1 haploinsufficiency. The c.1138+1G>T mutation is expected to produce a truncated protein. Heterozygous SF1 loss-of-function mutations in these cases resulted in mild DSD manifestations, such as dysgenetic testes, spontaneous puberty, and preserved adrenal function.

A recurrent p.Arg92Trp variant in steroidogenic factor-1 (NR5A1) can act as a molecular switch in human sex development.

Cell lineages of the early human gonad commit to one of the two mutually antagonistic organogenetic fates, the testis or the ovary. Some individuals with a 46,XX karyotype develop testes or ovotestes (testicular or ovotesticular disorder of sex development; TDSD/OTDSD), due to the presence of the testis-determining gene, SRY. Other rare complex syndromic forms of TDSD/OTDSD are associated with mutations in pro-ovarian genes that repress testis development (e.g. WNT4); however, the genetic cause of the more common non-syndromic forms is unknown. Steroidogenic factor-1 (known as NR5A1) is a key regulator of reproductive development and function. Loss-of-function changes in NR5A1 in 46,XY individuals are associated with a spectrum of phenotypes in humans ranging from a lack of testis formation to male infertility. Mutations in NR5A1 in 46,XX women are associated with primary ovarian insufficiency, which includes a lack of ovary formation, primary and secondary amenorrhoea as well as early menopause. Here, we show that a specific recurrent heterozygous missense mutation (p.Arg92Trp) in the accessory DNA-binding region of NR5A1 is associated with variable degree of testis development in 46,XX children and adults from four unrelated families. Remarkably, in one family a sibling raised as a girl and carrying this NR5A1 mutation was found to have a 46,XY karyotype with partial testicular dysgenesis. These unique findings highlight how a specific variant in a developmental transcription factor can switch organ fate from the ovary to testis in mammals and represents the first missense mutation causing isolated, non-syndromic 46,XX testicular/ovotesticular DSD in humans.

Identification of NR5A1 Mutations and Possible Digenic Inheritance in 46,XY Gonadal Dysgenesis

The phenotypic spectrum of patients carrying NR5A1 mutations ranges from 46,XY gonadal dysgenesis to male infertility. Phenotypic variability could be due to digenic or oligogenic inheritance of pathogenic variants in other testis-determining genes. Here, exome sequencing identified 2 pathogenic de novo NR5A1 mutations in 2 patients with 46,XY gonadal dysgenesis, p.Q206Tfs*20 and p.Arg313Cys. The latter patient also carried a missense mutation in MAP3K1. Our data extend the number of NR5A1 gene mutations associated with gonadal dysgenesis. The combination of an NR5A1 mutation with a MAP3K1 variant may explain the phenotypic variability associated with NR5A1 mutations.

Two novel mutations in the NR5A1 gene as a cause of disorders of sex development in a Pakistani cohort of 46,XYpatients.

NR5A1 plays a central role in gonadal development and regulation by transcriptional regulation of key modulators involved in steroidogenesis. Mutations in human NR5A1 are frequently associated with 46,XY disorders of sex development (DSD). We analysed a Pakistani cohort of patients with 46,XY DSD, presenting with variable degrees of gonadal dysgenesis, for NR5A1 mutations. The study identified three mutations (p.Tyr03X, p.Glu07X and p.Gln299HisfsX386), of which two are novel, in these patients with 46,XY DSD. The mutations, p.Tyr03X and novel p.Glu07X, are located in the coding region of the gene, corresponding to DNA-binding domain of the predicted protein. In silico analysis for the novel homozygous p.Gln299HisfsX386 mutation in ligand-binding domain of NR5A1 revealed subtle changes in overall tertiary conformation which is predicted to affect the normal physiology of this mutant protein. This study reveals two novel mutations with altered NR5A1 protein in twenty patients with 46,XY DSD, highlighting the critical role of NR5A1 protein in gonadal development and differentiation. In conclusion, the current and previous studies suggest that the NR5A1 mutations are present in around 8-15% of patients with 46,XY DSD presenting with gonadal dysgenesis. For the clinical utility of NR5A1 gene mutations, more comprehensive studies with large 46,XY DSD patient series in different populations are suggested.

Mutational screening of NR5A1 gene encoding steroidogenic factor 1 in cryptorchidism and male factor infertility and functional analysis of seven undescribed mutations

To study the role of NR5A1 in cryptorchidism and male factor infertility. Mutations in NR5A1 have been initially associated with primary adrenal insufficiency and 46,XY gonadal dysgenesis and more recently with less severe phenotypes, including preliminary descriptions in severe forms of male factor infertility. Far less clear is the possible involvement of NR5A1 mutations in cryptorchidism. Retrospective cross-sectional cohort study and functional analysis of mutant proteins. University department. Nine hundred fifty-nine subjects, including children with cryptorchidism and adults with different semen phenotypes associated or not associated with a history of cryptorchidism. None. Mutation screening of NR5A1 by sequencing all exons. Functional analysis of mutant proteins by transactivation assays of CYP11A1 and CYP17A1 promoters. We identified seven undescribed and one previously described missense mutation in subjects with severe spermatogenic impairment, without (4/236, 1.7%) and with (3/85, 3.5%) a history of cryptorchidism. Newborns with cryptorchidism carry NR5A1 mutations at low frequency (0.7%), whereas no mutations were found in milder forms of infertility and normozoospermia, irrespective of the presence of cryptorchidism. The mutant proteins showed impaired transactivation of gonadal promoters. A single nucleotide polymorphism (rs1110061; c.437 G→C; p.Gly146Ala) was also associated with more severe forms of spermatogenic impairment with cryptorchidism. This study, combined with what is already known about NR5A1-associated phenotypes, suggests considering mutations in this gene as a novel genetic cause of more severe forms of male factor infertility, especially when associated with a history of cryptorchidism.

LRH-1 May Rescue SF-1 Deficiency for Steroidogenesis: An in vitro and in vivo Study

Steroidogenic factor 1 (NR5A1/SF-1) mutations usually manifest in 46,XY individuals with variable degrees of disordered sex development and in 46,XX women with ovarian insufficiency. So far, there is no genotype-phenotype correlation. The broad spectrum of phenotype with NR5A1 mutations may be due to a second hit in a gene with similar function to NR5A1/SF-1. Liver receptor homologue-1 (LRH-1/NR5A2) might be a good candidate. We performed in vitro studies for the interplay between SF-1, LRH-1 and DAX-1, expression profiles in human steroidogenic tissues, and NR5A2 genetic studies in a cohort (11 patients, 8 relatives, 11 families) harboring heterozygote NR5A1/SF-1 mutations. LRH-1 isoforms transactivate the CYP17A1 and HSD3B2 promoters similarly to SF-1 and compensate for SF-1 deficiency. DAX-1 inhibits SF-1- and LRH-1-mediated transactivation. LRH-1 is found expressed in human adult and fetal adrenals and testes. However, no NR5A2/LRH-1 mutations were detected in 14 individuals with heterozygote NR5A1/SF-1 mutations. These findings demonstrate that in vitro LRH-1 can act like SF-1 and compensate for its deficiency. Expression of LRH-1 in fetal testis suggests a role in male gonadal development. However, as we found no NR5A2/LRH-1 mutations, the ‘second genetic hit' in SF-1 patients explaining the broad phenotypic variability remains elusive.

Extensive clinical, hormonal and genetic screening in a large consecutive series of 46,XY neonates and infants with atypical sexual development.

BackgroundOne in 4500 children is born with ambiguous genitalia, milder phenotypes occur in one in 300 newborns. Conventional time-consuming hormonal and genetic work-up provides a genetic diagnosis in around 20-40% of 46,XY cases with ambiguous genitalia. All others remain without a definitive diagnosis. The investigation of milder cases, as suggested by recent reports remains controversial.MethodsIntegrated clinical, hormonal and genetic screening was performed in a sequential series of 46, XY children, sex-assigned male, who were referred to our pediatric endocrine service for atypical genitalia (2007–2013).ResultsA consecutive cohort of undervirilized 46,XY children with external masculinization score (EMS) 2–12, was extensively investigated. In four patients, a clinical diagnosis of Kallmann syndrome or Mowat-Wilson syndrome was made and genetically supported in 2/3 and 1/1 cases respectively. Hormonal data were suggestive of a (dihydro)testosterone biosynthesis disorder in four cases, however no HSD17B3 or SRD5A2 mutations were found. Array-CGH revealed a causal structural variation in 2/6 syndromic patients. In addition, three novel NR5A1 mutations were found in non-syndromic patients. Interestingly, one mutation was present in a fertile male, underlining the inter- and intrafamilial phenotypic variability of NR5A1-associated phenotypes. No AR, SRY or WT1 mutations were identified.ConclusionOverall, a genetic diagnosis could be established in 19% of non-syndromic and 33% of syndromic cases. There is no difference in diagnostic yield between patients with more or less pronounced phenotypes, as expressed by the external masculinisation score (EMS). The clinical utility of array-CGH is high in syndromic cases. Finally, a sequential gene-by-gene approach is time-consuming, expensive and inefficient. Given the low yield and high expense of Sanger sequencing, we anticipate that massively parallel sequencing of gene panels and whole exome sequencing hold promise for genetic diagnosis of 46,XY DSD boys with an undervirilized phenotype.Electronic supplementary materialThe online version of this article (doi:10.1186/s13023-014-0209-2) contains supplementary material, which is available to authorized users.

Etiology of primary ovarian insufficiency in a series young girls presenting at a pediatric endocrinology center.

The cause of the primary ovarian insufficiency (POI) remains unknown in the majority of cases. A retrospective study was carried out in 17 girls with POI and normal 46,XX karyotype evaluated before 20 years of age. The etiology of POI was determined in eight girls (group 1) and remained idiopathic in nine girls (group 2). In group 1, five patients had a medical history: cerebellar ataxia due to congenital disorder of glycosylation (CDG) 1 in three cases, mitochondrial disease in one case, and autoimmune deficiencies in one case. The diagnosis of POI was made on pubertal delay or primary amenorrhea in these five patients, whilst the others presented with clitoral hypertrophy at birth or short stature and pubertal delay in two cases with NR5A1 mutation or with short stature and learning difficulties in one case with mitochondrial disease. In group 2, associated diseases were arthrogryposis malformative, gut, and bladder malformations and kidney failure or parieto-occipital tumor. The genes tested (NR5A1, BMP15, GDF9, and NOBOX) showed no mutation. The frequency of defined etiologies (47%) is high. This is probably because of the recruitment of the cases at the pediatric center, where other somatic anomalies can lead to the accurate determination of the etiology.