Prenatal Findings in Postnatal Cases of Disorders of Sex Development: Experience from a Tertiary-Specialized Center in Brazil.

INTRODUCTION AND OBJECTIVE: Prenatal suspicion of disorders/differences of sex development (DSDs) is a relatively new phenomenon. The aim of this study was to review the prenatal findings of DSD cases postnatally diagnosed in our tertiary referral center. METHODS: We evaluated 57 DSD cases with sex ambiguity who had undergone prenatal ultrasound with phenotypic sex assessment and/or cell-free fetal DNA (cffDNA) for genotypic sex assessment. RESULTS: Prenatal cffDNA had been performed in 32 cases, being positive (suggestive of male genotypic sex) in 26 and negative (suggestive of female genotypic sex) in 6. Five with cffDNA negative had a prenatal ultrasound indicating female external genitalia, in turn, in those with cffDNA positive, only two had a prenatal ultrasound indicating male external genitalia. Our postnatal data showed that when external genitalia were female or poorly virilized, prenatal ultrasound indicated female sex, but in cases of higher degree of virilization, ultrasound showed similar rates of male, female, or undetermined sex. Regarding the karyotype, our data showed those with XY karyotype had positive cffDNA, those with XX karyotype had negative cffDNA, and all five with sex chromosome anomalies had positive cffDNA because they were 45,X/46,XY. We suggested an algorithm to investigate these cases during gestation, including evaluation of uterus, fetal growth, and malformations. CONCLUSION: We suggest that the parents should be counseled prenatally by a dedicated multidisciplinary team with experience in DSD management and evaluated as soon as possible after birth.

DHX37 and the implications in Disorders of Sex Development: an update review.

BACKGROUND: DHX37 is an autosomal gene responsible for encoding a helicase from the DExD/H-box family that plays an essential role in ribosome biogenesis. Variants in this gene were previously reported in two different phenotypes: neurodevelopmental disorders and disorders/differences of sex development (DSD). Particularly for the DSD group, variants were mainly reported associated with gonadal dysgenesis and testicular regression syndrome. SUMMARY: Focusing specific in the DSD group, we revised the 21 DHX37 variants described across a total of 55 cases published in the literature so far. We summarized the most important clinical and molecular features of all cases, trying to have a better comprehensiveness about this gene in the sexual development. KEY MESSAGES: The trick question regarding DHX37 is how a helicase involved in basic cell function could have a specific role in testis development. Little is known about the impact of DHX37 variants in DSD individuals. Nevertheless, current research strongly suggests that DHX37 is involved in the male sex development pathway, particularly in testis determination and maintenance. This is evidenced by the predominant assignment of affected individuals as males and the presence of Wolffian structures in most of the cases. Advancements in molecular techniques, such as the generation of induced pluripotent stem cells, and the digenic inheritance for DHX37 cases, are also addressed in this paper. This represents the first comprehensive review of all DHX37 variants published in the literature to date.

DHX37 and NR5A1 Variants Identified in Patients with 46,XY Partial Gonadal Dysgenesis.

The group of disorders known as 46,XY gonadal dysgenesis (GD) is characterized by anomalies in testis determination, including complete and partial GD (PGD) and testicular regression syndrome (TRS). Several genes are known to be involved in sex development pathways, however approximately 50% of all cases remain elusive. Recent studies have identified variants in DHX37, a gene encoding a putative RNA helicase essential in ribosome biogenesis and previously associated with neurodevelopmental disorders, as a cause of PGD and TRS. To investigate the potential role of DHX37 in disorders of sexual development (DSD), 25 individuals with 46,XY DSD were analyzed and putative pathogenic variants were found in four of them. WES analyses were performed on these patients. In DHX37, the variant p.(Arg308Gln), recurrent associated with DSD, was identified in one patient; the p.(Leu467Val), predicted to be deleterious, was found together with an NR5A1 loss-of-function variant in patient 2; and, the p.(Val999Met) was identified in two unrelated patients, one of whom (patient 3) also carried a pathogenic NR5A1 variant. For both patients carrying DHX37 and NR5A1 pathogenic variants, a digenic inheritance is suggested. Our findings support the importance of DHX37 variants as a cause of disorders of sex development, implying a role in testis development.

SOX3 duplication in a boy with 46,XX ovotesticular disorder of sex development and his 46,XX sister with atypical genitalia: Probable germline mosaicism.

Ovotesticular disorders of sex development (OT-DSD) are characterized by ovarian follicles and seminiferous tubules in the same individual, with a wide range of atypical genitalia. We report on two sibs with atypical genitalia and SRY-negative 46,XX DSD, OT-DSD was confirmed only in the boy, while the girl had bilateral ovaries. Chromosome microarray analysis (CMA) showed a 737-kb duplication at Xq27.1 including the entire SOX3 gene in both sibs, which was confirmed by quantitative real time PCR. Also, X chromosome inactivation assay showed random inactivation in both sibs. Whole exome sequencing revealed no pathogenic or likely pathogenic variant. CMA of the parents showed normal results for both, suggesting that germline mosaicism could be the reason of recurrence of this duplication in the siblings. Our results support a pathogenic role of SOX3 overexpression in 46,XX subjects leading to variable DSD phenotypes.

Clinical and laboratory differences between chromosomal and undefined causes of non-obstructive azoospermia: A retrospective study

ABSTRACT BACKGROUND: Knowledge of clinical and laboratory differences between chromosomal and undefined causes aids etiological research on non-obstructive azoospermia. OBJECTIVE: Compare clinical and laboratory differences between men with non-obstructive azoospermia due to chromosomal anomalies versus undefined causes DESIGN AND SETTING: A cross-sectional retrospective study conducted at a public university hospital in Campinas (Brazil) METHODS: All men aged 20-40 years with non-obstructive azoospermia were included in the analysis. RESULTS: The 107 cases included 14 with Klinefelter syndrome (KS) (13%), 1 with mosaic KS, 4 with sex development disorders (2 testicular XX, 1 NR5A1 gene mutation, and 1 mild androgen insensitivity syndrome) (4%), 9 with other non-obstructive azoospermia etiologies (8%), and 79 with undefined causes. The 22 chromosomal anomaly cases (14 KS, 1 mosaic KS, 2 testicular XX, 4 sex chromosome anomalies, and 1 autosomal anomaly) were compared with the 79 undefined cause cases. The KS group had lower average testicular volume, shorter penile length, and lower total testosterone levels but greater height, arm span, serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels, and gynecomastia frequency (absent in the undefined group and affecting more than half of the KS group). Patients with testicular XX DSD had LH, FSH, and penile length data intermediate between the KS and undefined cause groups, testicular volume similar to the KS group, and other data similar to the undefined group. CONCLUSION: Clinical and laboratory data differentiate men with non-obstructive azoospermia and chromosomal anomalies, particularly KS and testicular XX, from those with undefined causes or other chromosomal anomalies.

Clinical and laboratory differences between chromosomal and undefined causes of non-obstructive azoospermia: A retrospective study.

BACKGROUND: Knowledge of clinical and laboratory differences between chromosomal and undefined causes aids etiological research on non-obstructive azoospermia. OBJECTIVE: Compare clinical and laboratory differences between men with non-obstructive azoospermia due to chromosomal anomalies versus undefined causes. DESIGN AND SETTING: A cross-sectional retrospective study conducted at a public university hospital in Campinas (Brazil). METHODS: All men aged 20-40 years with non-obstructive azoospermia were included in the analysis. RESULTS: The 107 cases included 14 with Klinefelter syndrome (KS) (13%), 1 with mosaic KS, 4 with sex development disorders (2 testicular XX, 1 NR5A1 gene mutation, and 1 mild androgen insensitivity syndrome) (4%), 9 with other non-obstructive azoospermia etiologies (8%), and 79 with undefined causes. The 22 chromosomal anomaly cases (14 KS, 1 mosaic KS, 2 testicular XX, 4 sex chromosome anomalies, and 1 autosomal anomaly) were compared with the 79 undefined cause cases. The KS group had lower average testicular volume, shorter penile length, and lower total testosterone levels but greater height, arm span, serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels, and gynecomastia frequency (absent in the undefined group and affecting more than half of the KS group). Patients with testicular XX DSD had LH, FSH, and penile length data intermediate between the KS and undefined cause groups, testicular volume similar to the KS group, and other data similar to the undefined group. CONCLUSION: Clinical and laboratory data differentiate men with non-obstructive azoospermia and chromosomal anomalies, particularly KS and testicular XX, from those with undefined causes or other chromosomal anomalies.

Bilateral Wilms' tumor in a child with Denys-Drash syndrome: novel frameshift variant disrupts the WT1 nuclear location signaling region.

OBJECTIVES: Wilm's Tumor (WT) is the most common pediatric kidney cancer. Whereas most WTs are isolated, approximately 5% are associated with syndromes such as Denys-Drash (DDS), characterized by early onset nephropathy, disorders of sex development and predisposition to WT. CASE PRESENTATION: A 46,XY patient presenting with bilateral WT and genital ambiguity without nephropathy was heterozygous for the novel c.851_854dup variant in WT1 gene sequence. This variant affects the protein generating the frameshift p.(Ser285Argfs*14) that disrupts a nuclear localization signal (NLS) region. CONCLUSIONS: This molecular finding is compatible with the severe scenario regarding the Wilm's tumor presented by the patient even though nephropathy was absent.

Leydig and Sertoli cell function in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion: a case-control study.

BACKGROUND: Because normal male sexual differentiation is more complex than normal female sexual differentiation, there are more cases of disorders of sex development (DSDs) with 46,XY karyotype that have unclear etiology. However, Leydig and Sertoli cell markers are rarely used in distinguishing such individuals. OBJECTIVES: To evaluate the function of Leydig and Sertoli cells in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion. STUDY DESIGN AND SETTING: Case-control study with 77 patients, including eight with partial androgen insensitivity syndrome, eight with 5α-reductase deficiency type 2 (5ARD2) and 19 with idiopathic 46,XY DSD, and 42 healthy controls, from the Interdisciplinary Study Group for Sex Determination and Differentiation (GIEDDS), at the State University of Campinas (UNICAMP), Campinas, Brazil. METHODS: Baseline levels of gonadotropins, anti-Müllerian hormone (AMH), inhibin B, insulin-like 3 (INSL3), testosterone and dihydrotestosterone in cases, and AMH, inhibin B, and INSL3 levels in controls, were assessed. RESULTS: There was no significant difference in age between cases and controls (P = 0.595). AMH and inhibin B levels were significantly lower in cases than in controls (P = 0.031 and P < 0.001, respectively). INSL3 levels were significantly higher in cases than in controls (P = 0.003). Inhibin B levels were lower in 5ARD2 patients (P = 0.045) and idiopathic patients (P = 0.001), in separate comparisons with the controls. CONCLUSION: According to our findings, we can speculate that inhibin B levels may be used to differentiate among DSD cases.

Leydig and Sertoli cell function in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion: a case-control study

Abstract BACKGROUND: Because normal male sexual differentiation is more complex than normal female sexual differentiation, there are more cases of disorders of sex development (DSDs) with 46,XY karyotype that have unclear etiology. However, Leydig and Sertoli cell markers are rarely used in distinguishing such individuals. OBJECTIVES: To evaluate the function of Leydig and Sertoli cells in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion. STUDY DESIGN AND SETTING: Case-control study with 77 patients, including eight with partial androgen insensitivity syndrome, eight with 5α-reductase deficiency type 2 (5ARD2) and 19 with idiopathic 46,XY DSD, and 42 healthy controls, from the Interdisciplinary Study Group for Sex Determination and Differentiation (GIEDDS), at the State University of Campinas (UNICAMP), Campinas, Brazil. METHODS: Baseline levels of gonadotropins, anti-Müllerian hormone (AMH), inhibin B, insulin-like 3 (INSL3), testosterone and dihydrotestosterone in cases, and AMH, inhibin B, and INSL3 levels in controls, were assessed. RESULTS: There was no significant difference in age between cases and controls (P = 0.595). AMH and inhibin B levels were significantly lower in cases than in controls (P = 0.031 and P < 0.001, respectively). INSL3 levels were significantly higher in cases than in controls (P = 0.003). Inhibin B levels were lower in 5ARD2 patients (P = 0.045) and idiopathic patients (P = 0.001), in separate comparisons with the controls. CONCLUSION: According to our findings, we can speculate that inhibin B levels may be used to differentiate among DSD cases.

Are NR5A1 Variations a Frequent Cause of 46,XX Ovotesticular Disorders of Sex Development? Analysis from a Single Center and Systematic Review.

INTRODUCTION: Ovotesticular disorder of sex development (OT-DSD) is a rare condition defined by concomitance of testicular tissue and ovarian tissue (containing follicles) in the same individual. In SRY-negative 46,XX OT-DSD, the presence of testicular tissue may be due to variations in NR5A1. Our aims were to search for NR5A1 variants in SRY-negative 46,XX OT-DSD patients and to perform a systematic review on the contribution of NR5A1 variations to 46,XX OT-DSD. METHODS: Sanger sequencing of NR5A1 was performed in seven SRY-negative 46,XX OT-DSD patients: five simplex cases and two with another sibling with a 46,XX DSD. Systematic review of original studies on NR5A1 sequencing of 46,XX OT-DSD patients was performed according to PRISMA-P guideline. Case reports were selected for analysis of clinical features. Individuals with NR5A1-associated testicular DSD were not included. RESULTS: Sanger sequencing of NR5A1 did not reveal pathogenic variants among our patients. Our cohort was included in this systematic review with seven other articles, totalizing fifty-six 46,XX OT-DSD patients investigated by Sanger or whole-exome sequencing. From them, three NR5A1 pathogenic variants were identified (5% of the cases). Clinical analysis of these 3 cases and 5 case reports revealed: predominance of ovotestis (13/16 gonads) and bilateral OT-DSD (5/8 cases). CONCLUSION: The etiology of most 46,XX OT-DSD cases remains elusive, highlighting the importance of a deeper molecular investigation.

Complete androgen insensitivity syndrome and risk of gonadal malignancy: systematic review.

Complete androgen insensitivity syndrome (CAIS) is a rare condition characterized by 46,XY karyotype, female external genitalia, absence of uterus, and testes located intra-abdominally, in the inguinal ring or in the labia majora. In the present study, the frequency of testicular malignancy in prepubertal and pubertal patients with CAIS who underwent gonadectomy or gonadal biopsy were evaluated. Systematic review was performed using electronic databases according to the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) guidelines. The samples included 15 articles published between 1998 and 2019. From a total of 456 patients who underwent gonadectomy or gonadal biopsy, 6.14% had a premalignant lesion and most were postpubertal (82.14%). A malignant lesion was found in 1.3% and all were postpubertal. Because the risk of malignancy is very low in prepubertal patients with CAIS, gonadectomy may be delayed until puberty is complete, allowing it to progress naturally; however, close follow-up of the patient is required.

Androgens by immunoassay and mass spectrometry in children with 46,XY disorder of sex development.

OBJECTIVE: Steroid measurement is a challenge in pediatric endocrinology. Currently, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is considered a gold standard for this purpose. The aim of this study was to compare both LC-MS/MS and immunoassay (IA) for androgens before and after human recombinant chorionic gonadotropin (rhCG) stimulus in children with 46,XY disorders of sex development (DSD). METHODS: Nineteen patients with 46,XY DSD were evaluated; all of them were prepubertal and non-gonadectomized. Testosterone, dihydrotestosterone (DHT), DHEA and androstenedione were measured by IA and LC-MS/MS before and 7 days after rhCG injection. The correlation between IA and LC-MS/MS was analyzed by the intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient (SCC). For concordance analysis the Passing and Bablok (PB) regression and the Bland and Altman (BA) method were used. RESULTS: Testosterone showed excellent correlation (ICC = 0.960 and SCC = 0.964); DHT showed insignificant and moderate correlations as indicated by ICC (0.222) and SCC (0.631), respectively; DHEA showed moderate correlation (ICC = 0.585 and SCC = 0.716); and androstenedione had poor and moderate correlations in ICC (0.363) and SCC (0.735), respectively. Using the PB method, all hormones showed a linear correlation, but proportional and systematic concordance errors were detected for androstenedione, systematic errors for testosterone and no errors for DHEA and DHT. By the BA method, there was a trend of IA to overestimate testosterone and androstenedione and underestimate DHEA and DHT when compared to LC-MS/MS. CONCLUSION: Traditional IA should be replaced by LC-MS/MS for the androgens measurement in prepubertal children whenever is possible.

Promises and pitfalls of whole-exome sequencing exemplified by a nephrotic syndrome family.

High-throughput techniques such as whole-exome sequencing (WES) show promise for the identification of candidate genes that underlie Mendelian diseases such as nephrotic syndrome (NS). These techniques have enabled the identification of a proportion of the approximately 54 genes associated with NS. However, the main pitfall of using WES in clinical and research practice is the identification of multiple variants, which hampers interpretation during downstream analysis. One useful strategy is to evaluate the co-inheritance of rare variants in affected family members. Here, we performed WES of a patient with steroid-resistant NS (SRNS) and intermittent microhematuria. Currently, 15 years after kidney transplantation, this patient presents normal kidney function. The patient was found to be homozygous for a rare MYO1E stop-gain variant, and was heterozygous for rare variants in NS-associated genes, COL4A4, KANK1, LAMB2, ANLN, E2F3, and APOL1. We evaluated the presence or absence of these variants in both parents and 11 siblings, three of whom exhibited a milder phenotype of the kidney disease. Analysis of variant segregation in the family, indicated the MYO1E stop-gain variant as the putative causal variant underlying the kidney disease in the patient and two of her affected sisters. Two secondary variants in COL4A4-identified in some other affected family members-require further functional studies to determine whether they play a role in the development of microhematuria in affected family members. Our data illustrate the difficulties in distinguishing the causal pathogenic variants from incidental findings after WES-based variant analysis, especially in heterogenous genetic conditions, such as NS.

Mutation update for the NR5A1 gene involved in DSD and infertility.

Nuclear receptor subfamily 5 group A member 1 (NR5A1), also named steroidogenic factor 1, is an essential transcription factor that regulates a number of target genes crucial for normal reproductive physiology and endocrine function. It is encoded by NR5A1 gene and is expressed in high doses mainly in steroidogenic tissues, where it controls several steps of adrenal and gonadal development. NR5A1 mutations are associated with a wide phenotypic spectrum of disorders/differences of sex development (DSD), a group of conditions in which development of chromosomal, gonadal, or anatomic sex is atypical. Here, we reviewed 188 NR5A1 mutations from 238 cases reported in literature so far. Additionally, we report the variations p.Ser4*, p.(Cys55Ser), p.(Met78Leu), and p.Met98Glyfs*45, which have not been annotated for NR5A1 before and were identified in some of the 205 46,XY patients of our own cohort. This is the first NR5A1 mutation review which includes both 46,XX and 46,XY karyotype, with the purpose of discussing the complexity of genotype-phenotype correlations among DSD and infertile male patients and also females with primary ovarian failure.

Early development of a gonadal tumor in a patient with mixed gonadal dysgenesis

SUMMARY A gonadal tumor was diagnosed in the first months of life in a patient with genital ambiguity, a 45,X/46,XY karyotype, and mixed gonadal dysgenesis. Gonadal biopsies at the age of 3 months revealed dysgenetic testes and a gonadoblastoma on the right testis. Even though gonadal tumors are rare in childhood, this case indicates that prophylactic removal of dysgenetic gonads should be performed as early as possible, especially when the female sex is assigned to a patient with a Y-chromosome sequence.

Three new Brazilian cases of 17α-hydroxylase deficiency: clinical, molecular, hormonal, and treatment features.

BACKGROUND: Deficiency of 17α-hydroxylase (17OHD) is a rare form of adrenal hyperplasia. Diagnosis is generally delayed, impairing appropriate treatment. CASE PRESENTATION: Here, we report the clinical, molecular, hormonal, and treatment data of three unrelated 17OHD patients, aged 14-16 years with hypergonadotrophic hypogonadism; uncontrolled hypertension; primary adrenal insufficiency; and high progesterone, low to normal potassium, and low dehydroepiandrosterone, androstenedione, and testosterone levels. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) at baseline and after an adrenocorticotropic hormone test showed low cortisol and cortisone and high deoxycorticosterone (DOC) and corticosterone levels; both DOC/21-deoxycortisol and costicosterone/cortisol ratios were very high. Patient 2 had 46,XX karyotype and patients 1 and 3, had 46,XY. A molecular analysis showed that two of the patients were homozygous for p.W406R mutation and the other patient was compound heterozygous for p.W406R and p.P428L. Hypertension was controlled only after the administration of both prednisone and mineralocorticoid antagonist. CONCLUSIONS: Hypertension in young women must lead to diagnostic suspicion, even in the pre-pubertal period. The basal level of progesterone is an indicator of 17OHD. Mineral and glucocorticoid ratios obtained from LC-MS/MS can reinforce the diagnosis. Hypertension can be controlled using glucocorticoid replacement therapy and mineralocorticoid antagonist.

FSH may be a useful tool to allow early diagnosis of Turner syndrome.

BACKGROUND: Ultrasensitive assays to measure pre-pubertal gonadotropins levels could help identify patients with Turner syndrome (TS) in mid-childhood, but studies in this field are scarce. The aim of this study was to analyze gonadotropins levels in girls with TS throughout childhood. METHODS: Retrospective longitudinal study conducted with 15 girls with TS diagnosed with < 5 years whose FSH and LH measures were available since then. Hormones were evaluated in newborn/mini-puberty (< 0.5 years), early childhood (0.5-5 years), mid-childhood (5-10 years) and late childhood/adolescence (> 10 years). In newborn/mini-puberty and late childhood/adolescence pre-pubertal or pubertal gonadotropins were considered normal; in early childhood and mid-childhood concentrations above the pre-pubertal range were considered abnormal. RESULTS: Abnormally high FSH alone was found in four of five patients in newborn/mini-puberty, 13 of 15 during early childhood and nine of 15 during mid-childhood. In the group of 12 patients in late childhood/adolescence, the three girls with spontaneous puberty had only normal levels; the remaining showed only post-menopausal concentrations. In mid-childhood one patient exhibited only pre-pubertal FSH. Conversely, most LH measurements in early and mid-childhood were normal. CONCLUSION: Karyotyping of girls with short stature and high FSH levels would allow early diagnosis of Turner syndrome in a significant number of patients, particularly when resources for chromosome study of all girls with growth deficiency are limited.

Comparison between two inhibin B ELISA assays in 46,XY testicular disorders of sex development (DSD) with normal testosterone secretion.

BACKGROUND: Inhibin B is a hormone produced by the Sertoli cells that can provide important information for the investigation of disorders of sex development (DSD) with 46,XY karyotype. The aim of this study is to compare two enzyme-linked immunosorbent assay (ELISA) assays for dosage of serum inhibin B in patients with 46,XY DSD with normal testosterone secretion. METHODS: Twenty-nine patients with 46,XY DSD and normal testosterone secretion (partial androgen insensitivity syndrome [PAIS] [n=8]; 5α-reductase deficiency [n=7] and idiopathic 46,XY DSD [n=14]) were included. Molecular analysis of the AR and SRD5A2 genes were performed in all patients and the NR5A1 gene analysis in the idiopathic group. Measurements of inhibin B were performed by two second-generation ELISA assays (Beckman-Coulter and AnshLabs). Assays were compared using the interclass correlation coefficient (ICC) and the Bland-Altman method. RESULTS: ICC was 0.915 [95% confidence interval (CI): 0.828-0.959], however, a discrepancy was observed between trials, which is more evident among higher values when analyzed by the Bland-Altman method. CONCLUSIONS: It is recommended to perform the inhibin B measurement always using the same ELISA kit when several evaluations are required for a specific patient.

Early development of a gonadal tumor in a patient with mixed gonadal dysgenesis.

A gonadal tumor was diagnosed in the first months of life in a patient with genital ambiguity, a 45,X/46,XY karyotype, and mixed gonadal dysgenesis. Gonadal biopsies at the age of 3 months revealed dysgenetic testes and a gonadoblastoma on the right testis. Even though gonadal tumors are rare in childhood, this case indicates that prophylactic removal of dysgenetic gonads should be performed as early as possible, especially when the female sex is assigned to a patient with a Y-chromosome sequence.

Functional characterization of five NR5A1 gene mutations found in patients with 46,XY disorders of sex development.

Steroidogenic factor-1 (SF1), encoded by the NR5A1 gene, is a key regulator of steroidogenesis and reproductive development. NR5A1 mutations described in 46,XY patients with disorders of sex development (DSD) can be associated with a range of conditions of phenotypes; however, the genotype-phenotype correlation remains elusive in many cases. In the present study, we describe the impact of five NR5A1 variants (three novel: p.Arg39Cys, p.Ser32Asn, and p.Lys396Argfs*34; and two previously described: p.Cys65Tyr and p.Cys247*) on protein function, identified in seven patients with 46,XY DSD. In vitro functional analyses demonstrate that NR5A1 mutations impair protein functions and result in the DSD phenotype observed in our patients. Missense mutations in the DNA binding domain and the frameshift mutation p.Lys396Argfs*34 lead to both, markedly affected transactivation assays, and loss of DNA binding, whereas the mutation p.Cys247* retained partial transactivation capacity and the ability to bind a consensus SF1 responsive element. SF1 acts in a dose-dependent manner and regulates a cascade of genes involved in the sex determination and steroidogenesis, but in most cases reported so far, still lead to a sufficient adrenal steroidogenesis and function, just like in our cases, in which heterozygous mutations are associated to 46,XY DSD with intact adrenal steroid biosynthesis.