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Adrenal hypoplasia congenita, attributed to NR0B1 pathogenic variants, accounts for more than 50% of the incidence of primary adrenal insufficiency in children. Although more than 250 different deleterious variations have been described, no genotype-phenotype correlation has been defined to date. We report a case of an adopted boy who reported the onset of an adrenal crisis at 2 weeks of age, requiring replacement therapy with mineralocorticoids and glucocorticoids for 4 months. For 3 years, he did well without treatment. At almost 4 years of age, the disorder was restarted. A long follow-up showed the evolution of hypogonadotropic hypogonadism. Molecular studies on NR0B1 revealed a novel and deleterious deletion-insertion-inversion-deletion complex rearrangement sorted in the 5'-3' direction, which is described as follows: (1) deletion of the intergenic region (between TASL and NR0B1 genes) and 5' region, (2) insertion of a sequence containing 37 bp at the junction of the intergenic region of the TASL gene and a part of exon 1 of the NR0B1 gene, (3) inversion of a part of exon 1, (4) deletion of the final portion of exon 1 and exon 2 and beginning of the 3'UTR region, (5) maintenance of part of the intergenic sequence (between genes MAGEB1 and NR0B1, telomeric sense), (6) large posterior deletion, in the same sense. The path to molecular diagnosis was challenging and involved several molecular biology techniques. Evaluating the breakpoints in our patient, we assumed that it was a nonrecurrent rearrangement that had not yet been described. It may involve a repair mechanism known as nonhomologous end-joining (NHEJ), which joins two ends of DNA in an imprecise manner, generating an "information scar," represented herein by the 37 bp insertion. In addition, the local Xp21 chromosome architecture with sequences capable of modifying the DNA structure could impact the formation of complex rearrangements.
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Insuficiência Adrenal , Receptor Nuclear Órfão DAX-1 , Pré-Escolar , Humanos , Masculino , Insuficiência Adrenal/genética , Insuficiência Adrenal/patologia , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/congênito , Receptor Nuclear Órfão DAX-1/genética , Seguimentos , Estudos de Associação Genética/métodos , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Hipoadrenocorticismo Familiar/genética , Mutação/genética , Fenótipo , Recém-Nascido , AdolescenteRESUMO
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.
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Feto , Aberrações dos Cromossomos Sexuais , Gravidez , Humanos , Masculino , Feminino , Brasil/epidemiologia , Genótipo , Diagnóstico Pré-NatalRESUMO
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.
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Mosaicismo , Transtornos Ovotesticulares do Desenvolvimento Sexual , Masculino , Feminino , Humanos , Transtornos Ovotesticulares do Desenvolvimento Sexual/diagnóstico , Transtornos Ovotesticulares do Desenvolvimento Sexual/genética , Transtornos Ovotesticulares do Desenvolvimento Sexual/patologia , Irmãos , Ovário/patologia , Células Germinativas/patologia , Fatores de Transcrição SOXB1/genéticaRESUMO
BACKGROUND: APOL1 high-risk genotypes (HRG) are associated with increased risk of kidney disease in individuals of African ancestry. We analyzed the effects of APOL1 risk variants on an ethnically diverse Brazilian pediatric nephrotic syndrome (NS) cohort. METHODS: Multicenter study including 318 NS patients, categorized as progressors to advanced CKD [estimated glomerular filtration rate (eGFR)] < 30 mL/min/1.73 m2] and slow/non-progressors (eGFR > 30 mL/min/1.73 m2 through the study). We employed Cox regression with progression time as the outcome and APOL1 genotype as the independent variable. We tested this association in the entire cohort and three subgroups; (1) focal segmental glomerulosclerosis (FSGS), (2) steroid-resistant NS (SRNS), and (3) those who underwent kidney biopsy. RESULTS: Nineteen patients (6%) had an HRG. Of these, 47% were self-reported White. Patients with HRG manifested NS at older ages and presented higher frequencies of FSGS and SRNS. HRG patients progressed to advanced CKD more often than low-risk-genotype (LRG) children in the whole NS cohort (p = 0.001) and the three subgroups. In SRNS and biopsied patients, a single risk variant was associated with trends of higher CKD progression risk. CONCLUSIONS: Novel discoveries include a substantial prevalence of HRG among patients self-reported White, worse kidney outcomes in HRG versus LRG children in the FSGS subgroup, and a trend of higher CKD progression risk associated with a single risk variant in the SRNS cohort. These findings suggest APOL1-associated NS extends beyond patients self-reported non-White, the HRG effect is independent of FSGS, and a single risk variant may have a detrimental impact in children with NS.
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Glomerulosclerose Segmentar e Focal , Síndrome Nefrótica , Insuficiência Renal Crônica , Apolipoproteína L1/genética , Criança , Receptores ErbB , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/genética , Humanos , Síndrome Nefrótica/genéticaRESUMO
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.
Assuntos
Exoma/genética , Síndrome Nefrótica/genética , Adulto , Feminino , Variação Genética/genética , Heterozigoto , Homozigoto , Humanos , Rim/patologia , Masculino , Linhagem , Fenótipo , Sequenciamento do Exoma/métodos , Adulto JovemRESUMO
BACKGROUND: Nephrotic syndrome is traditionally classified on the basis of the response to standard steroid treatment. Mutations in more than 24 genes have been associated with nephrotic syndrome in children, although the great majority of steroid-resistant cases have been attributed to mutations in three main genes: NPHS1, NPHS2 and WT1. The aims of this study were to identify mutations in these genes more frequently reported as mutated and to characterize each variation using different in silico prediction algorithms in order to understand their biological functions. METHODS: We performed direct sequence analysis of exons 8 and 9 of WT1, 8 exons of NPHS2 and 29 exons of NPHS1, including NPHS2 and NPHS1 intron-exon boundary sequences, as well as 700 bp of the 5' UTR from both genes in 27 steroid-resistant patients aged between 3 months and 18 years. RESULTS: Analysis of the NPHS2 gene revealed four missense mutations, one frameshift mutation and three variations in the 5' UTR. Four patients presented compound heterozygosis, and four other patients presented one heterozygous alteration only. WT1 and NPHS1 gene analysis did not reveal any mutations. DISCUSSION: This is the first study focusing on genetics of SRNS in Brazilian children. Identification of mutations is important because it could influence physicians' decision on patient treatment, as patients carrying mutations can be spared the side effects of immunosuppressive therapy and ultimately could be considered for kidney transplantation from a living donor. CONCLUSIONS: After molecular analysis of the genes more frequently reported as mutated in 27 steroid-resistant nephrotic syndrome patients, we identified NPHS2 mutations confirming the hereditary character of the kidney disease in only 14.8% of patients. Therefore, the next step is to perform a next generation sequencing based analysis of glomeluropathy-related panel of genes for the remaining patients in order to search for mutations in other genes related to steroid-resistant nephrotic syndrome.
Assuntos
Regiões 5' não Traduzidas/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Síndrome Nefrótica/genética , Adolescente , Sequência de Bases , Criança , Pré-Escolar , Biologia Computacional , Primers do DNA/genética , Mutação da Fase de Leitura/genética , Humanos , Lactente , Dados de Sequência Molecular , Mutação de Sentido Incorreto/genética , Análise de Sequência de DNA , Proteínas WT1/genéticaRESUMO
Retinitis pigmentosa is a group of genetically determined retinal dystrophies characterized by primary photoreceptor apoptosis and can occur in isolated or syndromic conditions. This study reviewed the clinical data of 15 patients with syndromic retinitis pigmentosa from a Rare Disease Reference Center in Brazil and the results of their next-generation sequencing tests. Five males and ten females participated, with the mean ages for ocular disease onset, fundoscopic diagnosis, and molecular evaluation being 9, 19, and 29 years, respectively. Bardet-Biedl syndrome (n = 5) and Usher syndrome (n = 3) were the most frequent diagnoses, followed by other rare conditions. Among the patients, fourteen completed molecular studies, with three negative results and eleven revealing findings in known genes, including novel variants in MKKS (c.432_435del, p.Phe144Leufs*14), USH2A (c.(7301+1_7302-1)_(9369+1_9370-1)del), and CEP250 (c.5383dup, p.Glu1795Glyfs*13, and c.5050del, p.Asp1684Thrfs*9). Except for Kearn-Sayre, all presented an autosomal recessive inheritance pattern with 64% homozygosity results. The long gap between symptom onset and diagnosis highlights the diagnostic challenges faced by the patients. This study reaffirms the clinical heterogeneity of syndromic retinitis pigmentosa and underscores the pivotal role of molecular analysis in advancing our understanding of these diseases.
Assuntos
Retinose Pigmentar , Humanos , Retinose Pigmentar/genética , Retinose Pigmentar/patologia , Retinose Pigmentar/diagnóstico , Masculino , Feminino , Adulto , Adolescente , Criança , Adulto Jovem , Síndromes de Usher/genética , Síndromes de Usher/patologia , Síndromes de Usher/diagnóstico , Brasil/epidemiologia , Pessoa de Meia-Idade , Sequenciamento de Nucleotídeos em Larga Escala , Síndrome de Bardet-Biedl/genética , MutaçãoRESUMO
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.
RESUMO
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.
Assuntos
Transtornos do Desenvolvimento Sexual , Transtornos Ovotesticulares do Desenvolvimento Sexual , Fator Esteroidogênico 1 , Humanos , Masculino , Transtornos do Desenvolvimento Sexual/genética , Transtornos do Desenvolvimento Sexual/patologia , Gônadas , Metanálise como Assunto , Transtornos Ovotesticulares do Desenvolvimento Sexual/genética , Transtornos Ovotesticulares do Desenvolvimento Sexual/patologia , Fator Esteroidogênico 1/genética , Testículo/patologiaRESUMO
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.
Assuntos
Azoospermia , Síndrome de Klinefelter , Masculino , Humanos , Azoospermia/genética , Estudos Retrospectivos , Estudos Transversais , Hormônio Foliculoestimulante , Testosterona , Recuperação Espermática , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/genética , Hormônio LuteinizanteRESUMO
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.
Assuntos
Síndrome de Denys-Drash , Neoplasias Renais , Tumor de Wilms , Criança , Síndrome de Denys-Drash/genética , Síndrome de Denys-Drash/patologia , Genes do Tumor de Wilms , Heterozigoto , Humanos , Neoplasias Renais/genética , Proteínas WT1/genética , Tumor de Wilms/genéticaRESUMO
SUMMARY: Denys-Drash syndrome (DDS, Online Mendelian Inheritance in Man number 194080) is a rare human developmental disease generally occurring in 46,XY individuals characterized by the combination of disorder of sex development, early onset nephropathy, and Wilms' tumor (WT). DDS is mainly caused by mutations in the WT1 gene. This report describes a novel WT1 gene mutation in a DDS patient. Sequencing the WT1 gene revealed a heterozygous transversion CAT>AAT within exon 8, causing the substitution of an asparagine for a histidine at residue 377. The p.H377N mutation is predicted to diminish the WT1 protein DNA-binding affinity as it might disrupt the normal zinc finger 2 conformation.
Assuntos
Síndrome de Denys-Drash/genética , Genes do Tumor de Wilms , Síndrome de Denys-Drash/complicações , Transtornos do Desenvolvimento Sexual/genética , Evolução Fatal , Humanos , Lactente , Recém-Nascido , Neoplasias Renais/genética , Masculino , Mutação Puntual , Reação em Cadeia da Polimerase , Tumor de Wilms/genéticaRESUMO
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.
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Nephrotic syndrome is one of the most common kidney pathologies in childhood, being characterized by proteinuria, edema, and hypoalbuminemia. In clinical practice, it is divided into two categories based on the response to steroid therapy: steroid-sensitive and steroid resistant. Inherited impairments of proteins located in the glomerular filtration barrier have been identified as important causes of nephrotic syndrome, with one of these being podocin, coded by NPHS2 gene. NPHS2 mutations are the most frequent genetic cause of steroid resistant nephrotic syndrome. The aim of this review is to update the list of NPHS2 mutations reported between June 2013 and February 2017, with a closer look to mutations occurring in Latin American countries.
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Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Mutação/genética , Geografia , Humanos , América LatinaRESUMO
Frasier syndrome (FS) is characterized by gonadal dysgenesis and nephropathy. It is caused by specific mutations in the Wilms' tumor suppressor gene (WT1) located in 11p23. Patients with the 46,XY karyotype present normal female genitalia with streak gonads, and have higher risk of gonadal tumor, mainly, gonadoblastoma. Therefore, elective bilateral gonadectomy is indicated. Nephropathy in FS consists in nephrotic syndrome (NS) with proteinuria that begins early in childhood and progressively increases with age, mainly due to nonspecific focal and segmental glomerular sclerosis (FSGS). Patients are generally unresponsive to steroid and immunosuppressive therapies, and will develop end-stage renal failure (ESRF) during the second or third decade of life. We report here four cases of FS diagnosis after identification of WT1 mutations. Case 1 was part of a large cohort of patients diagnosed with steroid-resistant nephrotic syndrome, in whom the screening for mutations within WT1 8-9 hotspot fragment identified the IVS9+5G>A mutation. Beside FS, this patient showed unusual characteristics, such as urinary malformation (horseshoe kidney), and bilateral dysgerminoma. Cases 2 and 3, also bearing the IVS9+5G>A mutation, and case 4, with IVS9+1G>A mutation, were studied due to FSGS and/or delayed puberty; additionally, patients 2 and 4 developed bilateral gonadal tumors. Since the great majority of FS patients have normal female external genitalia, sex reversal is not suspected before they present delayed puberty and/or primary amenorrhea. Therefore, molecular screening of WT1 gene is very important to confirm the FS diagnosis.
Assuntos
Síndrome de Frasier/genética , Mutação/genética , Proteínas WT1/genética , Adolescente , Criança , Pré-Escolar , Feminino , Síndrome de Frasier/diagnóstico , Gonadoblastoma/genética , Humanos , Neoplasias Ovarianas/genéticaRESUMO
AIM: To present phenotypic variability of WT1-related disorders. METHODS: Description of clinical and genetic features of five 46,XY patients with WT1 anomalies. RESULTS: Patient 1: newborn with genital ambiguity; he developed Wilms tumor (WT) and chronic renal disease and died at the age of 10 months; the heterozygous 1186G>A mutation compatible with Denys-Drash syndrome was detected in this child. Patients 2 and 3: adolescents with chronic renal disease, primary amenorrhea and hypergonadotrophic hypogonadism; patient 2 had a gonadoblastoma. The heterozygous IVS9+4, C>T mutation, compatible with Frasier syndrome was detected. Patient 4: 9-year-old boy with aniridia, genital ambiguity, dysmorphisms and mental deficiency; a heterozygous 11p deletion, compatible with WAGR syndrome was detected. Patient 5: 2 months old, same diagnosis of patient 4; he developed WT at the age of 8 months. CONCLUSIONS: Constitutional abnormalities of WT1 cause gonadal and renal anomalies and predisposition to neoplasia and must be investigated in patients with ambiguous genitalia, chronic renal disease and(or) Wilms tumors; primary amenorrhea with chronic renal disease; and aniridia, genital ambiguity and dysmorphisms.
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Síndrome de Frasier , Genes do Tumor de Wilms , Neoplasias Renais , Proteínas WT1/genética , Adolescente , Amenorreia/diagnóstico , Criança , Evolução Fatal , Feminino , Síndrome de Frasier/diagnóstico , Síndrome de Frasier/genética , Genitália/anormalidades , Genitália/patologia , Heterozigoto , Humanos , Lactente , Recém-Nascido , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Masculino , Fenótipo , Insuficiência Renal Crônica/diagnósticoRESUMO
Frasier syndrome (FS) is characterized by gonadal dysgenesis and nephropathy. It is caused by specific mutations in the Wilms' tumor suppressor gene (WT1) located in 11p23. Patients with the 46,XY karyotype present normal female genitalia with streak gonads, and have higher risk of gonadal tumor, mainly, gonadoblastoma. Therefore, elective bilateral gonadectomy is indicated. Nephropathy in FS consists in nephrotic syndrome (NS) with proteinuria that begins early in childhood and progressively increases with age, mainly due to nonspecific focal and segmental glomerular sclerosis (FSGS). Patients are generally unresponsive to steroid and immunosuppressive therapies, and will develop end-stage renal failure (ESRF) during the second or third decade of life. We report here four cases of FS diagnosis after identification of WT1 mutations. Case 1 was part of a large cohort of patients diagnosed with steroid-resistant nephrotic syndrome, in whom the screening for mutations within WT1 8-9 hotspot fragment identified the IVS9+5G>A mutation. Beside FS, this patient showed unusual characteristics, such as urinary malformation (horseshoe kidney), and bilateral dysgerminoma. Cases 2 and 3, also bearing the IVS9+5G>A mutation, and case 4, with IVS9+1G>A mutation, were studied due to FSGS and/or delayed puberty; additionally, patients 2 and 4 developed bilateral gonadal tumors. Since the great majority of FS patients have normal female external genitalia, sex reversal is not suspected before they present delayed puberty and/or primary amenorrhea. Therefore, molecular screening of WT1 gene is very important to confirm the FS diagnosis. Arq Bras Endocrinol Metab. 2012;56(8):525-32.
A síndrome de Frasier (SF), caracterizada por disgenesia gonadal e nefropatia, é causada por mutações específicas no gene supressor do tumor de Wilms (WT1) localizado em 11p23. Pacientes com cariótipo 46,XY apresentam genitália feminina normal com gônadas disgenéticas e alto risco de tumor gonadal, principalmente o gonadoblastoma. Por isso, a gonadectomia bilateral eletiva está indicada. A nefropatia na SF consiste de síndrome nefrótica com proteinúria que se inicia na infância e aumenta progressivamente com a idade, principalmente devido à glomeruloesclerose focal e segmentar (GESF). Esses pacientes não respondem ao tratamento com esteroides e imunossupressores e desenvolverão insuficiência renal crônica durante a segunda ou terceira década de vida. Neste trabalho, são relatados quatro casos de SF cujo diagnóstico foi definido após o rastreamento molecular do gene WT1. O caso 1 faz parte de um grande grupo de pacientes que tiveram diagnóstico de síndrome nefrótica corticorresistente e no qual o rastreamento de mutações no fragmento 8-9 do gene WT1 identificou a mutação IVS9+5G>A. Além da SF, essa paciente apresentou características incomuns, tais como malformação urinária (rins em ferradura) e disgerminoma bilateral. Os casos 2 e 3 também apresentaram a mutação IVS9+5G>A, e, no caso 4, foi identificada a mutação IVS9+1G>A, sendo que esses três casos foram encaminhados para estudo molecular em decorrência de GESF e/ou atraso no desenvolvimento puberal. Além disso, as pacientes 2 e 4 desenvolveram tumor gonadal bilateral. Visto que a maioria dos pacientes com SF apresenta genitália externa feminina, não há suspeita de sexo reverso até apresentarem atraso puberal e/ou amenorreia primária. Portanto, o rastreamento molecular do gene WT1 é de fundamental importância para se confirmar o diagnóstico de SF. Arq Bras Endocrinol Metab. 2012;56(8):525-32.
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Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Síndrome de Frasier/genética , Mutação/genética , Proteínas WT1/genética , Síndrome de Frasier/diagnóstico , Gonadoblastoma/genética , Neoplasias Ovarianas/genéticaRESUMO
AIM: To present phenotypic variability of WT1-related disorders. METHODS: Description of clinical and genetic features of five 46,XY patients with WT1 anomalies. RESULTS: Patient 1: newborn with genital ambiguity; he developed Wilms tumor (WT) and chronic renal disease and died at the age of 10 months; the heterozygous 1186G>A mutation compatible with Denys-Drash syndrome was detected in this child. Patients 2 and 3: adolescents with chronic renal disease, primary amenorrhea and hypergonadotrophic hypogonadism; patient 2 had a gonadoblastoma. The heterozygous IVS9+4, C>T mutation, compatible with Frasier syndrome was detected. Patient 4: 9-year-old boy with aniridia, genital ambiguity, dysmorphisms and mental deficiency; a heterozygous 11p deletion, compatible with WAGR syndrome was detected. Patient 5: 2 months old, same diagnosis of patient 4; he developed WT at the age of 8 months. CONCLUSIONS: Constitutional abnormalities of WT1 cause gonadal and renal anomalies and predisposition to neoplasia and must be investigated in patients with ambiguous genitalia, chronic renal disease and(or) Wilms tumors; primary amenorrhea with chronic renal disease; and aniridia, genital ambiguity and dysmorphisms.
OBJETIVO: Descrever a variabilidade fenotípica das anomalias relacionadas ao WT1. MÉTODOS: Descrição das características clínicas e genéticas de cinco pacientes 46,XY com anomalias no WT1. RESULTADOS: Paciente 1: Recém-nascido com ambigüidade genital desenvolveu tumor de Wilms (TW) e insuficiência renal crônica (IRC), com óbito aos 10 meses. Detectada a mutação 1186G>A em heterozigose, compatível com síndrome de Denys-Drash. Pacientes 2 e 3: Adolescentes com IRC, amenorréia primária e hipogonadismo hipergonadotrófico; a paciente 2 apresentava gonadoblastoma. Ambas apresentavam mutação IVS9+4, C>T em heterozigose, característica da síndrome de Frasier. Paciente 4: Idade 9 anos, aniridia, ambigüidade genital, dismorfismos e deficiência mental; deleção 11p, compatível com síndrome WAGR foi encontrada em heterozigose. Paciente 5: Dois meses, mesmo diagnóstico do paciente 4, desenvolveu TW aos 8 meses. CONCLUSÕES: Alterações constitucionais do WT1 determinam anomalias gonadais, renais e predisposição a neoplasias; devem ser pesquisadas em casos de ambigüidade genital associada a IRC e(ou) TW; de amenorréia primária com IRC; e aniridia, ambigüidade genital e dismorfismos.