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STUDY QUESTIONCan whole-exome sequencing (WES) reveal a shared pathogenic variant responsible for primary gonadal failure in both male and female patients from a consanguineous family?SUMMARY ANSWERPatients with primary ovarian insufficiency (POI) and non-obstructive azoospermia (NOA) were homozygous for the rare missense variant p. S754L located in the highly conserved MSH4 MutS signature motif of the ATPase domain. An oligozoospermic patient was heterozygous for the variant.WHAT IS KNOWN ALREADYMSH4 is a meiosis-specific protein expressed at a certain level in the testes and ovaries. Along with its heterodimer partner MSH5, it is responsible for double-strand Holliday junction recognition and stabilization, to ensure accurate chromosome segregation during meiosis. Knockout male and female mice for Msh4 and Msh5 are reportedly infertile due to meiotic arrest. In humans, MSH4 is associated with male and female gonadal failure, with distinct variations in the MutS domain V.STUDY DESIGN, SIZE, DURATIONThis was a retrospective genetics study of a consanguineous family with multiple cases of gonadal failure in both genders. The subject family was recruited in Iran, in 2018.PARTICIPANTS/MATERIALS, SETTING, METHODSThe proband who is affected by POI, an NOA brother, a fertile sister and their parents were subjected to WES. The discovered variant was validated in these individuals, and the rest of the family was also genotyped by Sanger sequencing. The variant was not detected in 800 healthy Iranian individuals from the Iranome database nor in 30 sporadic NOA and 30 sporadic POI patients. Suggested effect in aberrant splicing was studied by RT-PCR. Moreover, protein homology modeling was used to further investigate the amino acid substitution in silico.MAIN RESULTS AND THE ROLE OF CHANCEThe discovered variant is very rare and has never been reported in the homozygous state. It occurs in the ATPase domain at Serine 754, the first residue within the highly conserved MutS signature motif, substituting it with a Leucine. All variant effect prediction tools indicated this variant as deleterious. Since the substitution occurs immediately before the Walker B motif at position 755, further investigations based on protein homology were conducted. Considering the modeling results, the nature of the substituted amino acid residue and the distances between p. S754L variation and the residues of the Walker B motif suggested the possibility of conformational changes affecting the ATPase activity of the protein.LARGE SCALE DATAWe have submitted dbSNP entry rs377712900 to ClinVar under SCV001169709, SCV001169708 and SCV001142647 for oligozoospermia, NOA and POI, respectively.LIMITATIONS, REASONS FOR CAUTIONStudies in model organisms can shed more light on the role of this variant as our results were obtained by variant effect prediction tools and protein homology modeling.WIDER IMPLICATIONS OF THE FINDINGSIdentification of variants in meiotic genes should improve genetic counseling for both male and female infertility. Also, as two of our NOA patients underwent testicular sperm extraction (TESE) with no success, ruling out the existence of pathogenic variants in meiotic genes in such patients prior to TESE could prove useful.STUDY FUNDING/COMPETING INTEREST(S)This study was financially supported by Royan Institute in Tehran, Iran, and Institut Pasteur in Paris, France. The authors declare no competing interests.TRIAL REGISTRATION NUMBERN/A

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.

International audience; Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1 Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor β-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.

Background Central precocious puberty (CPP) results from early reactivation of the hypothalamic-pituitary-gonadal (HPG) axis. Four monogenic causes of CPP have been described (KISS, KISS1R MKRN3 and DLK1). Rare loss-of-function mutations of DLK1, a maternally imprinted gene located on chromosome 14q32.2, were identified in families with CPP. Both inherited or de novo DLK1 mutations were described in these affected families. Objective To investigate genetic abnormalities in the DLK1 in a French cohort of patients with idiopathic CPP. Patients: Genomic DNA was obtained from 122 patients (99 girls and 23 boys) with sporadic or familial CPP. Automatic sequencing of the coding regions of DLK1 gene (5 exons, using Sanger method) was performed in all cases, including 91 familial and 31 sporadic cases. Results A pathogenic heterozygous variant in the DLK1 gene (c.372C>A p.Cys124Ter (rs749564412) was identified in a girl with sporadic CPP associated with overweight. This nonsense mutation was considered rare (gnomAD total population 1/251,082) and it was located in the third EGF-like repeat domain in the extracellular region. The affected girl had progressive breast development at 4.5 years and accelerated growth velocity. She had breast development Tanner stage 4 at 5.5 years and bone age (BA) was 6 yr. Her height was 114.5 cm and BMI 18.16 (BMI Z-score = 2.48). Basal LH and FSH was 0.6 IU/L and 5.7 IU/L, respectively. GnRH-stimulated LH and FSH peaks were 14 IU/L and 18 IU/L, respectively, with LH: FSH ratio of 0.77. Other hormonal results were normal (estradiol: 11 pg/mL; ACTH: 11 pg/mL; IGF-1: 235 ng/mL; cortisol: 77 ng/mL). Brain MRI was normal. Pelvic ultrasound revealed uterus length: 49 mm, mucosal thickness of 4 mm, ovaries 20 and 25 mm with follicles less than 10 mm. She was treated with a depot GnRH analog (triptorelin). The DLK1 variant was inherited from her asymptomatic father who had a height of 181 cm. Familial history of CPP history was denied. Conclusion DLK1 loss-of-function are rare genetic cause of familial or sporadic CPP. Novel genetic findings in this factor reinforce its role in the physiopathology of the premature HPG axis reactivation and precocious sexual development in humans. Presentation: Saturday, June 11, 2022 12:45 p.m. - 1:00 p.m.

During embryonic development, mutually antagonistic signaling cascades determine the fate of the bipotential gonad towards a testicular or ovarian identity. Errors in this process result in human Disorders of Sex Development (DSDs), where there is discordance between chromosomal, gonadal, and anatomical sex. The absence of an appropriate, accessible in-vitro system is a major obstacle in understanding mechanisms of sex-determination/DSDs. Here, we describe protocols for differentiation of mouse and human pluripotent cells towards gonadal progenitors. Transcriptomic analysis reveals that the in-vitro-derived murine gonadal cells are equivalent to E11.5 in-vivo progenitors. Using similar conditions, Sertoli-like cells derived from 46,XY human induced pluripotent stem cells (hiPSCs) exhibit sustained expression of testis-specific genes, secrete AMH, migrate and form tubular structures. The cells derived from a 46,XY DSD female hiPSCs, carrying a NR5A1 variant, show aberrant gene expression and absence of tubule formation. CRISPR/Cas9-mediated correction of the variant rescued the phenotype. This is a robust tool to understand mechanisms of sex-determination and model DSDs.

International audience; Disorders/differences of sex development (DSD) comprise a group of congenital disorders that affect the genitourinary tract and usually involve the endocrine and reproductive system. The aim of this work was to identify genetic variants responsible for disorders of human urogenital development in a cohort of Egyptian patients. This three-year study included 225 patients with various DSD forms, referred to the genetic DSD and endocrinology clinic, National Research Centre, Egypt. The patients underwent thorough clinical examination, hormonal and imaging studies, detailed cytogenetic and fluorescence in situ hybridization analysis, and molecular sequencing of genes known to commonly cause DSD including AR, SRD5A2, 17BHSD3, NR5A1, SRY, and WT1. Whole exome sequencing (WES) was carried out for 18 selected patients. The study revealed a high rate of sex chromosomal DSD (33%) with a wide array of cytogenetic abnormalities. Sanger sequencing identified pathogenic variants in 33.7% of 46,XY patients, while the detection rate of WES reached 66.7%. Our patients showed a different mutational profile compared with that reported in other populations with a predominance of heritable DSD causes. WES identified rare and novel pathogenic variants in NR5A1, WT1, HHAT, CYP19A1, AMH, AMHR2, and FANCA and in the X-linked genes ARX and KDM6A. In addition, digenic inheritance was observed in two of our patients and was suggested to be a cause of the phenotypic variability observed in DSD.

Significance Sex development involves a precise spatiotemporal expression and interactions of numerous genetic factors, including the WT1 (Wilms tumor 1) gene. Complete and partial loss-of-function WT1 variants are associated with 46,XY disorders/differences of sex development (DSD). Some 46,XX individuals develop testis in absence of the testis-determining gene SRY. We describe a genotype/phenotype association where variants impacting the C-terminal zinc finger (ZF4) of WT1 cause testis development in 46,XX individuals. XX mice carrying a pathogenic variant of ZF4 display masculinization of the fetal gonads. Testis formation may be due to inappropriate interaction between the mutated WT1 and an essential ovarian determinant β-CATENIN. These data show that variants affecting a specific domain of a developmental transcription factor can switch organ fate., Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms’ tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10−6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10−4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor β-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.

International audience; Nuclear receptor subfamily 5 group A member 1/Steroidogenic factor 1 (NR5A1; SF-1; Ad4BP) mutations cause 46,XY disorders of sex development (DSD), with phenotypes ranging from developmentally mild (e.g., hypospadias) to severe (e.g., complete gonadal dysgenesis). The molecular mechanism underlying this spectrum is unclear. During sex determination, SF-1 regulates SOX9 (SRY [sex determining region Y]-box 9) expression. We hypothesized that SF-1 mutations in 46,XY DSD patients affect SOX9 expression via the Testis-specific Enhancer of Sox9 core element, TESCO. Our objective was to assess the ability of 20 SF-1 mutants found in 46,XY DSD patients to activate TESCO. Patient DNA was sequenced for SF-1 mutations and mutant SF-1 proteins were examined for transcriptional activity, protein expression, sub-cellular localization and in silico structural defects. Fifteen of the 20 mutants showed reduced SF-1 activation on TESCO, 11 with atypical sub-cellular localization. Fourteen SF-1 mutants were predicted in silico to alter DNA, ligand or cofactor interactions. Our study may implicate aberrant SF-1-mediated transcriptional regulation of SOX9 in 46,XY DSDs.

Fanconi anemia (FA) is a pleiotropic condition with 2 characteristic phenotypic markers of hematological and cytogenetic changes. The phenotype of patients with FA is very heterogeneous, associated with an array of congenital malformations affecting the skeletal, renal, genital, and/or central nervous systems. Here, we report on a 46,XY female who presented with gonadal dysgenesis and microcephaly. Exome sequencing showed that she was homozygous for a rare variant in the FANCA gene (c.4232C>T, p.P1411L, rs201494304). Both parents were heterozygous for the mutation. The FA mutation was associated with an atypical clinical presentation, and thus exome sequencing provided essential data that otherwise would have been overlooked in the diagnosis of this patient.

International audience; Recently, an autosomal recessive disorder including the triad of microcephaly, infantile epileptic encephalopathy, and permanent neonatal diabetes syndrome (MEDS, OMIM#614231) has emerged as a new distinguishing syndrome. Eight cases of whom seven from Arab countries, have been reported in association with biallelic variants in the IER3IP1 gene (Immediate early response-3 interacting protein-1). Here, we describe a Tunisian boy who presented with permanent neonatal diabetes, microcephaly, generalized seizures and hypovirilized external genitalia consisting of a small genitalia and unilateral cryptorchidism. Chromosomal analysis indicated a 46, XY karyotype in all metaphases. Exome sequencing identified a homozygous missense variant (c.62 T > G; p. Val21Gly) in the IER3IP1 gene, that is predicted to alter the protein structure within the hydrophobic/transmembrane. This variant was previously reported in two cases associated with MEDS. This is the first reported case of MEDS in Tunisia. Our report focuses on the IER3IP1 related phenotypic spectrum and assumes abnormal genitalia as part of the syndrome. Consequently, we recommend to perform hormonal testing on this topic to understand the effect of the IER3IP1 variant on the male genital pathway.

We report 2 families with undiagnosed recessive presynaptic congenital myasthenic syndrome (CMS). Whole exome or genome sequencing identified segregating homozygous variants in VAMP1: c.51_64delAGGTGGGGGTCCCC in a Kuwaiti family and c.146G>C in an Israeli family. VAMP1 is crucial for vesicle fusion at presynaptic neuromuscular junction (NMJ). Electrodiagnostic examination showed severely low compound muscle action potentials and presynaptic impairment. We assessed the effect of the nonsense mutation on mRNA levels and evaluated the NMJ transmission in VAMP1lew/lew mice, observing neurophysiological features of presynaptic impairment, similar to the patients. Taken together, our findings highlight VAMP1 homozygous mutations as a cause of presynaptic CMS. Ann Neurol 2017;81:597–603

Human sex determination (SD) involves complex mutually antagonistic genetic interactions of testis- and ovary-determining pathways. For many years, both male and female SD were considered to be regulated by a linear cascade of pro-male and pro-female genes, respectively; however, it has become clear that male and female development is achieved through the repression of the alternative state. A gene determining the formation of a testis may function by repressing the female state and vice versa. Uniquely in development, SD is achieved by suppression of the alternate fate and maintained in adulthood by a mutually antagonistic double-repressive pathway. Here, we review genetic data generated through large-scale sequencing approaches that are changing our view of how this system works, including the recently described recurrent NR5A1 p.R92W mutation associated with testis development in 46,XX children. We also review some of the unique challenges in the field to establish that mutations, such as this are pathogenic. The impending surge of new genetic data on human SD from sequencing projects will create opportunities for the development of mechanistic models that will clarify how the system operates and importantly provide data to understand how selection and developmental processes interact to direct the evolution of SD across species.

WT1 gene mutations have been described in 46,XY patients with ambiguous genitalia or complete gonadal dysgenesis with or without Wilms' tumor, nephropathy, gonadoblastoma, and other defects, e.g., cryptorchidism or hypospadias. p.R462W is a hot spot mutation in exon 9 and is the most common mutation in patients with Denys-Drash syndrome. However, in this study we report an Egyptian patient with a novel phenotype carrying the p.R462W mutation. We also review the heterogeneity of phenotypes of previously reported patients with the p.R462W (previously referred to as Arg394Trp) mutation.

Anti-müllerian hormone (AMH) is produced by Sertoli cells and signals through 2 transmembrane receptors (AMHR), specific types I and II, leading to regression of müllerian ducts during fetal male sex differentiation. Mutations in AMH and AMHR2 lead to the persistence of müllerian ducts in males which is transmitted in a recessive pattern. Here, we report 2 Egyptian DSD (disorder of sex development) patients reared as males who presented with bilateral cryptorchidism and otherwise normal male external genitalia and who both had a 46,XY karyotype. The first patient presented at the age of 2 years. Laparoscopic surgery revealed a uterus and fallopian tubes with the presence of 2 gonads, and biopsy and pathology revealed prepubertal testicular tissue showing small-sized tubules with mostly Sertoli cells and very few spermatogonia, edematous stroma, and no detectable ovarian tissue. The second patient presented at the age of 3 years. Laparoscopic surgery revealed a uterus and fallopian tubes, and serum AMH was very low (0.1 ng/mL). Molecular studies revealed a novel missense mutation in the AMHR2 gene in the first patient (c.767A>C; p.H256P) and a novel frameshift mutation in the AMH gene in the second patient (c.203delC; p.L70Cfs*7). We conclude that persistent müllerian ducts should be included in the differential diagnosis of cryptorchidism.

Aromatase deficiency (AD) is a very rare disorder resulting from mutations in the CYP19A1 gene encoding aromatase, a cytochrome P450 enzyme that plays a pivotal role in androgen conversion to estrogens. AD is inherited in an autosomal recessive trait, and to date only 35 cases have been described in the literature. Herein, we depict a new patient reared as a male, who presented at the age of 21 years with no palpable testis, hypoplastic scrotum, penis-like phallus (3 cm), and penoscrotal hypospadias. The patient was born to consanguineous parents, his karyotype was 46,XX, and SRY was negative. Pelvic sonar showed a small hypoplastic uterus, and no testis could be identified. Serum testosterone was within the reference range of females along with high gonadotropins. Pathology of gonadal biopsy showed ovarian stroma negative for oocytic follicle consistent with streak gonads. All these data were suggestive of AD, which was subsequently confirmed by molecular investigation of the CYP19A1 gene. A homozygous splice site mutation in the donor splice site of exon 9 was identified, c.1263 + 1G>T. This is the first report of such a rare disorder in an Egyptian patient. Our results reinforce the importance of considering AD in patients with 46,XX disorders of sex development after ruling out congenital adrenal hyperplasia.

R-spondin proteins are secreted agonists of canonical WNT/β-catenin signaling. Homozygous RSPO1 mutations cause a syndrome of 46,XX disorder of sexual development (DSD), palmoplantar keratoderma (PPK), and predisposition to squamous cell carcinoma. We report exome sequencing data of two 46,XX siblings, one with testicular DSD and the other with suspected ovotesticular DSD. Both have PPK and hearing impairment and carried a novel homozygous mutation c.332G>A (p.Cys111Tyr) located in the highly conserved furin-like cysteine-rich domain-2 (FU-CRD2). Cysteines in the FU-CRDs are strictly conserved, indicating their functional importance in WNT signaling through interaction with the leucine-rich repeat-containing G-protein-coupled receptors. This is the first RSPO1 missense mutation reported in association with human disease.

Mutation of the Wilms tumor suppressor gene (WT1) has been recognized as one of the etiologies of steroid-resistant nephrotic syndrome (SRNS). The mutation is also responsible for gonadal dysgenesis in 46,XY individuals. Early recognition of the presence of Y chromosome is of particular importance because of the high risk of gonadal tumor. We present here three cases of steroid-resistant nephrotic syndrome with WT1 mutation and 46,XY karyotype. Patient 1 and 2 have intron splice site (IVS9+5G A) mutation. Patient 3 has c.1301GA (p. R434H) mutation. All cases had normal female external genitalia at birth and eluded the diagnosis of gonadal dysgenesis until later in life. We suggest that chromosomal analysis should be promptly performed in female patients with early-onset steroid-resistant nephrotic syndrome. .

Introduction Un nouveau syndrome [OMIM#609382], a transmission autosomique recessive, a ete recemment decrit dans les pays arabes a forte consanguinite associant la triade microcephalie, epilepsie et le diabete neonatal permanant(MEDS). A notre connaissance, seuls huit patients ont ete rapportes et presentant une mutation au niveau du gene IER3IP1. Ici, Nous rapportons les caracteristiques cliniques et les resultats moleculaires d’un patient Tunisien atteint du MEDS afin de delimiter le spectre clinique et etablir une correlation genotype-phenotype. Observations Il s’agit d’un garcon âge de 3 ans issu d’un mariage consanguin. Il presente une dysmorphie faciale moderee, une microcephalie et une epilepsie et un desordre de developpement sexuel de type micropenis et ectopie testiculaire unilaterale. Le patient a beneficie d’une exploration par caryotype et par la technique de sequencage d’Exome. Le caryotype du patient est revenu normal 46,XY. Le sequencage d’Exome a revele une mutation faux-sens homozygote c.62T > G(p.Val21Gly) au niveau de l’exon 1 du gene IER3IP1. Discussion Toute alteration de la proteine ier3ip1 perturbe la reponse des cellules au stress du reticulum endoplasmique et conduit a un desequilibre entre l’apoptose et la proliferation cellulaire au niveau des cellules beta pancreatique et du cortex cerebral, mecanisme par lequel le diabete et la microcephalie pourraient etre developpes. Notre etude expose une eventuelle implication de l’hypogonadisme dans le developpement du MEDS, ce qui nous incite a mieux delimiter les manifestations cliniques de MEDS dans le cadre d’un conseil genetique precis. Ainsi, d’autres etudes complementaires sont indispensables pour mieux comprendre la physiopathologie du MEDS.

International audience; Differences of sex development are conditions with discrepancies between chromosomal, gonadal and phenotypic sex. In congenital hypogonadotropic hypogonadism, a lack of gonadotropin activity results primarily in the absence of pubertal development with prenatal sex development being (almost) unaffected in most patients. To expedite progress in the care of people affected by differences of sex development and congenital hypogonadotropic hypogonadism, the European Union has funded a number of scientific networks. Two Actions of the Cooperation of Science and Technology (COST) programmes - DSDnet (BM1303) and GnRH Network (BM1105) - provided the framework for ground-breaking research and allowed the development of position papers on diagnostic procedures and special laboratory analyses as well as clinical management. Both Actions developed educational programmes to increase expertise and promote interest in this area of science and medicine. In this Perspective article, we discuss the success of the COST Actions DSDnet and GnRH Network and the European Reference Network for Rare Endocrine Conditions (Endo-ERN), and provide recommendations for future research.

International audience; R-spondin proteins are secreted agonists of canonical WNT/β-catenin signaling. Homozygous RSPO1 mutations cause a syndrome of 46,XX disorder of sexual development (DSD), palmoplantar keratoderma (PPK), and predisposition to squamous cell carcinoma. We report exome sequencing data of two 46,XX siblings, one with testicular DSD and the other with suspected ovotesticular DSD. Both have PPK and hearing impairment and carried a novel homozygous mutation c.332G>A (p.Cys111Tyr) located in the highly conserved furin-like cysteine-rich domain-2 (FU-CRD2). Cysteines in the FU-CRDs are strictly conserved, indicating their functional importance in WNT signaling through interaction with the leucine-rich repeat-containing G-protein-coupled receptors. This is the first RSPO1 missense mutation reported in association with human disease.

Introduction: Next Generation Sequencing is revolutionising our understanding of variation in the human genome and as costs reduce the sequencing of patient’s genomes is become more routine.Areas covered: Here, we review the current challenges in the field and some of the efforts that are underway to resolve them. We describe how these technologies are impacting on our understanding of human sex development and the profound clinical implications of these technologies on conditions such as Disorders of Sex Development (DSD).Expert commentary: The sheer wealth of genomic data is generating new challenges—some are technical such as variant calling, or predicting the functional consequence of a variant—whereas others are more profound, such as establishing the link between extensive genomic information and the clinical presentation. Predicting disease phenotypes from genetic sequences is often extremely difficult because the genotype-phenotype relationship has proven to be far more complex than antici...

Congenital heart diseases (CHDs) are the most common cause of all birth defects and account for nearly 25% of all major congenital anomalies leading to mortality in the first year of life. Extracardiac anomalies including urogenital aberrations are present in ∼30% of all cases. Here, we present a rare case of a 46,XY patient with CHD associated with ambiguous genitalia consisting of a clitoris-like phallus and a bifid scrotum. Exome sequencing revealed novel homozygous mutations in the FGFR1 and STARD3 genes that may be associated with the phenotype.

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.

Sperm DNA methylation abnormalities have been detected in oligozoospermic men. However, the association between sperm DNA methylation defects, sperm parameters and sperm DNA, and chromatin integrity remains poorly understood. This study was designed to clarify this issue. We recruited a cohort of 92 men (62 normozoospermic and 30 oligoasthenozoospermic) presenting for infertility evaluation during a 1-year period. Sperm global DNA methylation was evaluated by an ELISA-like method, DNA fragmentation was evaluated by flow cytometry-based terminal transferase dUTP nick end-labeling (TUNEL) assay (reported as DNA fragmentation index or DFI), and sperm denaturation was evaluated by aniline blue staining (reported as sperm denaturation index or SDI, a marker of chromatin compaction). We found a significant positive association between sperm global DNA methylation level and conventional sperm parameters (sperm concentration and motility), supported by the results of methylation analysis on H19-DMR. We also identified significant inverse relationships between sperm global DNA methylation, and, both DFI and SDI. However, sperm global DNA methylation level was not related to sperm vitality or morphology. Our findings suggest that global sperm DNA methylation levels are related to conventional sperm parameters, as well as, sperm chromatin and DNA integrity.

WT1 gene mutations have been described in 46,XY patients with ambiguous genitalia or complete gonadal dysgenesis with or without Wilms' tumor, nephropathy, gonadoblastoma, and other defects, e.g., cryptorchidism or hypospadias. p.R462W is a hot spot mutation in exon 9 and is the most common mutation in patients with Denys-Drash syndrome. However, in this study we report an Egyptian patient with a novel phenotype carrying the p.R462W mutation. We also review the heterogeneity of phenotypes of previously reported patients with the p.R462W (previously referred to as Arg394Trp) mutation.

Objective To evaluate the carrier frequency of the pathogenic c.144delC mutation in AURKC gene and the contribution of this mutation in male infertility in a Moroccan population. Design Sanger sequencing of exon 3 in AURKC gene in infertile and control patients in Morocco. Setting Research institute. Patient(s) A total of 326 idiopathic infertile patients, and 450 age-related men. Intervention(s) The incidence of AURKC c.144delC mutation was determined in men with unexplained spermatogenic failure and a control cohort of normospermic fertile men. Main Outcome Measure(s) Genomic DNA was extracted from peripheral blood lymphocytes and the screening of the c.144delC mutation in AURKC gene performed by polymerase chain reaction and sequencing. Result(s) The c.144delC mutation in AURKC gene was found in patients at homozygous and heterozygous states, with an allelic frequency of 2.14%, whereas in controls this mutation was found only in the heterozygous state, with lower frequency (1%). Homozygous patients were characterized by macrocephalic and multiflagellar spermatozoa. Conclusion(s) Our data indicate that the AURKC c.144delC mutation has a relatively high carrier frequency in the Moroccan population; thus, we recommend screening for this deletion in infertile men with a high percentage of large-headed and multiflagellar spermatozoa.

International audience; Located at the cross-road between Europe and Africa, Tunisia is a North African country of 11 million inhabitants. Throughout its history, it has been invaded by different ethnic groups. These historical events, and consanguinity, have impacted on the spectrum and frequency of genetic diseases in Tunisia. Investigations of Tunisian families have significantly contributed to elucidation of the genetic bases of rare disorders, providing an invaluable resource of cases due to particular familial structures (large family size, consanguinity and share of common ancestors). In the present study, we report on and review different aspects of consanguinity in the Tunisian population as a case study, representing several features common to neighboring or historically related countries in North Africa and the Middle East. Despite the educational, demographic and behavioral changes that have taken place during the last four decades, familial and geographical endogamy still exist at high frequencies, especially in rural areas. The health implications of consanguinity in Tunisian families include an increased risk of the expression of autosomal recessive diseases and particular phenotypic expressions. With new sequencing technologies, the investigation of consanguineous populations provides a unique opportunity to better evaluate the impact of consanguinity on the genome dynamic and on health, in addition to a better understanding of the genetic bases of diseases. © 2014 S. Karger AG, Basel.

Disorders of sex development (DSD) are defined as 'congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical' [Lee et al., Pediatrics 2006;118:e488-e500]. Studies conducted in Western countries, with low rates of consanguinity, show that truly ambiguous genitalia have an estimated incidence of 1:5,000 births. There are indications that the prevalence of DSD is higher in endogamous communities. The incidence of ambiguous genitalia in Saudi Arabia has been estimated at 1:2,500 live births; whilst in Egypt, it has been estimated at 1:3,000 live births. This may be due in part to an increase in disorders of androgen synthesis associated with 46,XX DSD. There is clearly a need for further studies to address the frequency of DSD in communities with high levels of consanguinity. This will be challenging, as an accurate diagnosis is difficult and expensive even in specialized centres. In developing countries with high levels of consanguinity, these limitations can be compounded by cultural, social and religious factors. Overall there is an indication that consanguinity may lead to an increase in incidences of both 46,XY and 46,XX DSD, and a co-ordinated study of populations with higher incidences of consanguinity/endogamy is needed to resolve this.

The objective of this study was to identify disease-causing mutations in a Sri Lankan male child presenting with ambiguous genitalia and psychomotor delay using the exome sequencing approach. A novel mutation in the aristaless-related homeobox (ARX) gene causing a hemizygous nucleotide substitution in exon 5 was identified (NM_139058.2 (ARX): c.1614G>T; p.K538N). This change causes a nonsynonymous substitution in the aristaless domain within the ARX protein which is predicted to be deleterious. This is the first reported case of ambiguous genitalia and psychomotor delay associated with this novel missense mutation within the ARX protein, and it highlights the value of exome sequencing even in sporadic cases.

Temozolomide is an oral alkylating agent with proven efficacy in recurrent high-grade glioma. The antitumour activity of this molecule is attributed to the inhibition of replication through DNA methylation. However, this methylation may also perturb other DNA-dependent processes, such as spermatogenesis. The ability to father a child may be affected by having this treatment. Here we report a pregnancy and a baby born after 6 cures of temozolomide.The quality of gametes of the father has been studied through these cures and after the cessation of treatment. Sperm parameters, chromosomal content and epigenetic profiles of H19, MEST and MGMT have been analysed.Sperm counts decrease significantly and hypomethylation of the H19 locus increase with time even staying in the normal range.This is the first report of an epigenetic modification in sperm after temozolomide treatment suggesting a potential risk for the offspring. A sperm cryopreservation before the initiation of temozolomide treatment should be recommended.

The human Y chromosome is essential for human sex determination and spermatogenesis. The long arm contains the azoospermia factor (AZF) region. Microdeletions in this region are responsible for male infertility. The objective of this study was to determine the frequency of Y microdeletions in Algerian infertile males with azoospermia and oligoasthenoteratozoospermia syndrome (OATS) and to compare the prevalence of these abnormalities with other countries and regions worldwide. A sample of 80 Algerian infertile males with a low sperm count (1-20 × 106 sperms/ml) as well as 20 fertile male controls was screened for Y chromosome microdeletions. 49 men were azoospermic and 31 men had OATS. Genomic DNA was isolated from blood and polymerase chain reaction was carried out with a set of 6 AZFa, AZFb and AZFc STS markers to detect the microdeletions as recommended by the European Academy of Andrology. Among the 80 infertile men screened for microdeletion, 1 subject was found to have microdeletions in the AZFc (sY254 and sY255) region. The deletion was found in azoospermic subjects (1/49, 2%). The overall AZF deletion frequency was low (1/80, 1.3%). AZF microdeletions were observed neither in the OATS group nor in the control group. The frequency of AZF microdeletions in infertile men from Algeria was comparable to those reported in the literature. We suggest analyzing 6 STS in the first step to detect Y microdeletions in our population.

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.

In this review we will consider the gene mutations responsible for the non-syndromic forms of disorders of sex development (DSD) and how recent genetic findings are providing insights into the mechanism of sex determination. High-throughput sequencing technologies are having a major impact on our understanding of the genetic basis of rare human disorders, including DSD. The study of human DSD is progressively revealing subtle differences in the genetics of the sex-determining system between the mouse and the human. This plasticity of the sex-determining pathway is apparent in (a) the difference in phenotypes in human and mouse associated with the same gene, (b) the different gene regulatory mechanisms between human and mouse, and finally (c) the different and unexpected reproductive phenotypes seen in association with mutations in well-studied sex-determining genes.

Background Skin cancers (SC) are complex diseases that develop from complex combinations of genetic and environmental risk factors. One of the most severe and rare genetic diseases predisposing to SC is the Xeroderma pigmentosum (XP) syndrome. Objectives First, to identify the genetic etiology of XP and to better classify affected patients. Second, to provide early molecular diagnosis for pre-symptomatic patient and finally to offer genetic counseling for related individuals. Methods Whole Exome Sequencing (WES) and Run Of Homozygosity (ROH) were performed for two patients belonging to two different multiplex consanguineous families. The identified mutations were confirmed by Sanger sequencing and researched in ten Tunisian families including a total of 25 affected individuals previously suspected as having XP group V (XP-V) form. All patients had mild dermatological manifestations, absence of neurological abnormalities and late onset of skin tumors. Results Screening for functional variations showed the presence of the ERCC2 p.Arg683Gln in XP14KA-2 patient and a novel mutation, DDB2 p. (Lys381Argfs*2), in XP51-MAH-1 patient. Sanger sequencing and familial segregation showed that the ERCC2 mutation is present at a homozygous state in 10 affected patients belonging to 3 families. The second mutation in DDB2, is present at a homozygous state in 5 affected cases belonging to the same family. These two mutations are absent in the remaining 10 affected patients. The ERCC2 c.2048G > A mutation is present in a medium ROH region (class B) suggesting that it mostly arises from ancient relatedness within individuals. However, the c.1138delG DDB2 mutation is present in a large ROH region (class C) suggesting that it arises from recent relatedness. Conclusion To our knowledge, this is the first study that identifies XP-D and XP-E complementation groups in Tunisia. These two groups are very rare and under-diagnosed in the world and were not reported in North Africa.

Background The mechanism that initiates the onset of puberty is largely unknown but the age of onset is mainly under genetic control and influenced by environmental factors including nutrition. The coexistence in the same family of central precocious puberty and advanced puberty, both representing early puberty, suggests that they may represent a clinical spectrum of the same trait due to early activation of the GnRH pulse generator. We therefore evaluated the mode of inheritance of early puberty in a large series of familial cases. Methods A retrospective, single center study was carried out on 154 probands (116 girls and 38 boys), from 139 families seen for idiopathic central precocious puberty (onset before 8 years in girls and 9–10 years in boys, n = 93) and/or advanced puberty (onset between 8 and 10 years in girls and 10 and 11 years in boys, n = 61) seen over a period of 8 years. Results Of the 139 families, 111 (80.4 %) had at least one affected 1st degree relatives, 17 (12 %) had only 2nd, 5 (3.6 %) only 3rd and 3 (2.2 %) had both 2nd and 3rd degree affected individuals. In the two remaining families, the unaffected mother had affected girls from two unaffected fathers. In the majority of families the inheritance of the phenotype was consistent with autosomal dominant mode of transmission with incomplete penetrance. An exclusively maternal mode of transmission could be observed or inferred in 83 families, paternal in only 2 families (p

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.

Background The mechanism that initiates the onset of puberty is largely unknown but the age of onset is mainly under genetic control and influenced by environmental factors including nutrition. Familial forms of constitutional delay of puberty (CDP) suggest the involvement of genetic factors. The purpose of this study is to describe the presentation and the mode of inheritance of CDP in a series of familial cases. Methods A retrospective, single center study was carried out over 10 years on 48 probands (14 girls and 34 boys) from 48 families seen for CDP with a familial component. Results Of the 48 probands, 46 (96 %) had at least one affected 1st degree relatives and 2 (4 %, 2 boys) had only 2nd degree relatives affected. In girls, 11 families (79 %) exhibited exclusive maternal inheritance, 1 (7 %) paternal inheritance and 2 (14 %) both maternal and paternal inheritance. In boys, 14 families (41 %) exhibited exclusive maternal inheritance, 12 (35 %) paternal inheritance and 8 (24 %) both maternal and paternal inheritance. In the boys with bilineal inheritance, the ages at onset of puberty (16 ± 1.41 years) and at evaluation (16.05 ± 2.47 years) were higher than in those with unilineal inheritance (15.25 ± 0.35 and 15.1 ± 0.42 years respectively), but the difference was not significant. Conclusions In girls exclusive maternal inheritance seems to be the major mode of inheritance whereas for boys the mode of inheritance was almost equally maternal, paternal or bilineal. Clinical phenotype of boys with bilineal inheritance seems to be more severe, but the difference did not reach statistical significance, perhaps because of the small sample size. This greater severity of the phenotype in boys with bilineal inheritance is likely due to inheriting different puberty timing genes from each parent. Future research should be directed at identifying such genes.

Mullerian agenesis, also termed the Mayer–Rokitansky–Kuster–Hauser syndrome (MRKHS) is a disorder with an incidence of approximately 1 in 4500 newborn girls. This study screened 12 patients with MRKHS for mutations in two genes, LAMC1 and DLGH1 , involved in the development of Mullerian structures and found 10 previously described variants and no novel variants in the coding sequence. It is highly unlikely that these variants are pathological since these are common in the general population. It is the first time that an extensive study of LAMC1 and DLGH1 has been undertaken in patients with MRKHS. The data support the notion that mutations in the coding sequence of LAMC1 and DLGH1 may not be associated with MRKHS.

We screened 100 individuals with anomalies of testicular development or function for mutations in the TSPYL1 gene. A 46,XY female with complete gonadal dysgenesis carried a p.K320R mutation in the highly conserved NAP domain, and a 46,XY male with idiopathic azoospermia harbored a p.R89H mutation, and this data supports the hypothesis that mutations in TSPYL1 may contribute to anomalies of testicular development/function.

L’insuffisance ovarienne primaire (IOP) se caracterise par un arret de la fonction ovarienne normale avant l’âge de 40 ans. Elle touche environ 1 % des femmes avec souvent une transmission familiale evoquant une contribution genetique. NR5A1 est un recepteur nucleaire regulant la transcription de nombreux genes impliques dans le developpement sexuel et la reproduction. Plusieurs mutations dans le gene correspondant ont ete associees a des anomalies du developpement des surrenales ou des testicules. Nous avons identifie des mutations dans NR5A1 associees a une IOP incluant des cas 46,XX et 46,XY dans une meme famille. Ce gene joue donc un role important dans le developpement et le fonctionnement de l’ovaire. Cependant, plusieurs questions importantes demeurent. Quelle est la prevalence des mutations dans NR5A1 chez des patientes presentant diverses formes d’insuffisance ovarienne ? Quelles sont les correlations entre genotype et phenotype ? Y a-t-il une perte progressive de la fonction ovarienne chez les individus porteurs de mutations dans NR5A1 ? La reponse a ces questions permettra une meilleure comprehension du fonctionnement ovarien conduisant a l’elaboration de nouveaux outils diagnostiques et therapeutiques.

The aim of this study is to determine if Müllerian agenesis has a genetic basis linked to the WNT genes. Genomic DNA analyses for mutations in the coding sequences of four members of this family in a series of 11 women with Mayer-Rokitansky-Kuster-Hauser syndrome found four variants in the coding sequence of these genes, but causal mutations were not observed. This supports the hypothesis that mutations in the coding sequence of WNT4, WNT5A, WNT7A, and WNT9B are not responsible for the Mayer-Rokitansky-Kuster-Hauser syndrome.

Primary ovarian insufficiency, also known as premature ovarian failure, is characterized by loss of function of the ovaries before the age 40. Observational evidence of familial associations suggests a genetic basis for ovarian insufficiency. Despite extensive research, specific genetic causes have not been identified. A nuclear receptor, NR5A1, also called Ad4 binding protein or steroidogenic factor 1, is a protein that regulates the transcription of genes involved in the hypothalamic―pituitary―steroidogenic axis that play a key role in sexual development and reproduction. NR5A1 I is expressed in multiple ovarian cell types during fetal development, postnatal and prepubertal growth, and at maturity. In this study, the investigators tested the hypothesis that mutations in NR5A1 are associated with disorders of ovarian development and function. NR5A1 was sequenced in affected study subjects who were members of 4 families with a history of 46,XY disorders of sex development and 46,XX ovarian insufficiency and 25 women with 46,XX sporadic ovarian insufficiency. A panel of 1465 subjects of various ancestral origins who did not carry NRSA1 mutations served as controls. There was no clinical evidence of adrenal insufficiency among any of the affected patients. Mutations in the NR5A1 gene were found among members of each of the 4 families and 2 of the 25 subjects with isolated ovarian insufficiency. Analysis of the NRSA1 gene revealed a series of in-frame, frame-shift and missense mutations. Testing the effect of each of the NRSA1 mutations on protein function revealed a severe quantitative impairment of NRSA1 transactivational activity. A range of ovarian anomalies, including 46,XY gonadal dysgenesis and 46,XX primary ovarian insufficiency, were associated with the mutations. None of these mutations were found in any of the unaffected control subjects. These findings indicate that mutations in NRSA1 are associated with a number of ovarian anomalies characterized by loss of ovarian reproductive capacity.

BACKGROUND: Deletions in the azoospermia factor (AZF) region of the Y chromosome are frequent in infertile men. The clinical consequences and the mode of inheritance of these deletions are not yet clear. METHODS: Y chromosome deletion mapping and quantitative PCR analysis of the DAZ-gene copy number, supplemented with haplogroup typing in deleted patients, were performed, in combination with clinical assessments in 264 fathers and their sons conceived by assisted reproduction techniques (ART), and in 168 fertile men with normal sperm concentration. RESULTS: In the ART fathers group, a complete AZFc deletion was detected in 0.4% (1/264). AZFc rearrangements/polymorphisms were found in 6.8% (18/264; 95% CI: 4.4-10.5), which was significantly more frequent (P = 0.021) than in the controls (3/168; 1.8%, 95% CI: 0.6-5.1). All deletions were transmitted to the sons, without any clinical symptoms in early childhood. In the fathers, there was no significant correlation between the DAZ copy number and the severity of spermatogenic failure. CONCLUSIONS: AZFc rearrangements/polymorphisms are transmitted to sons and may represent a risk factor for decreased testis function and male subfertility, which needs confirmation in further studies in larger cohorts. However, deletions of two DAZ gene copies are compatible with normal spermatogenesis and fertility.

Le chromosome Y humain contient de nombreux genes et familles de genes necessaires a la spermatogenese. La majeure partie de ces genes est localisee au sein de sequences repetees frequemment soumises a des rearrangements. Les deletions des regions AZFa, AZFb et AZFc sont retrouvees chez 10 a 15 % des hommes presentant une oligozoospermie severe ou une azoospermie. Plusieurs deletions partielles de la region AZFc ont ete decrites. L'une d'entre elles emporte la moitie des genes de la region AZFc. Ses consequences sur la fertilite dans la population eurasienne semblent nulles ou minimes. Une autre deletion partielle denommee gr/gr emporte plusieurs genes de la region AZFc et a ete proposee comme un facteur de risque d'infertilite. Neanmoins, cette relation causale n'est pas evidente car il existe en fait plusieurs varietes de deletions gr/gr et leur repartition varie considerablement en fonction des origines ethniques et geographiques. Ces deletions semblent fixees sur certaines lignees de chromosome Y et n'auraient que peu ou pas d'influence sur la fertilite. La majorite des donnees concernant l'organisation chromosomique et le contenu genique du chromosome Y a ete deduite de la sequence de reference du chromosome Y deposee dans la base de donnees du NCBI. L'etablissement de donnees sur ce type de rearrangement dans la population generale n'a ete que recemment mis en œuvre. Ces etudes recentes ont souligne l'extreme diversite des polymorphismes de structure du chromosome Y dans la population generale. Correler ces polymorphismes de structure a la variabilite phenotypique sera l'enjeu de futures etudes. Il est vraisemblable que ces etudes aboutiront a la caracterisation non plus d'une sequence de reference unique du chromosome Y mais de plusieurs sequences de reference.