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1.
Artículo en Inglés | MEDLINE | ID: mdl-38874686

RESUMEN

PURPOSE: To define the spectrum of germline pathogenic variants (PVs) and copy number variant (CNV) in cancer susceptibility genes to the burden of breast and ovarian cancer (BC, OvC) in high-risk Brazilians in Minas Gerais with health insurance, southeast Brazil, undergoing multigene panel testing (MGPT). METHODS: Genotyping eligible individuals with health insurance in the Brazilian healthcare system for Hereditary Breast and Ovarian Cancer Syndrome to undergo molecular testing for 44 or 141-gene panels, a decision that was insurance driven. RESULTS: Overall, 701 individuals clinically defined as high BC/OvC risk, underwent MGPT from 1/2021 to 10/2022, with ~ 50% genotyped with a 44-gene panel and the rest with a 141-gene panel. Overall, 16.4% and 22.6% of genotyped individuals harbored PVs using 44-gene and the 141 gene panel, respectively. The most frequently mutated genes were: BRCA2 (3.7%); BRCA1 (3.6%) and monoallelic MUTYH (3.1%). CONCLUSION: The rate of PVs detected in high-risk individuals in this study was twice the 10% threshold used in Brazilian health guidelines. MGPT doubled the detection rate of PVs in cancer susceptibility genes in high-risk individuals compared with BRCA1/BRCA2 genotyping alone. The spectrum of PVs in Southern Brazil is diverse, with few recurring variants such as TP53 (0.6%), suggesting regional founder effects. The use of MGPT in hereditary cancer in Minas Gerais significantly increased the detection rate of P/LPVs compared to existing guidelines and should be considered as the primary genotyping modality in assessing hereditary cancer risk in Brazil.

2.
Ital J Pediatr ; 48(1): 89, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35689291

RESUMEN

BACKGROUND: The Congenital Adrenal Hyperplasia due to 21 hydroxylase deficiency is the most common cause of genital ambiguity in persons with XX sexual chromosomes. Genital ambiguity among persons with XY sexual chromosomes comprises diverse and rare etiologies. The deficiency of 17-beta-hydroxysteroid dehydrogenase type 3 enzyme (HSD17B3) is a rare autosomal recessive disorder due to functionally altered variants of the HSD17B3 gene. In this disorder/difference of sex development, the conversion of androstenedione into testosterone is impaired. The appearance of external genitalia of 46,XY individuals varies from typically male to almost female. CASE PRESENTATION: We report on a child presenting severe ambiguous genitalia. Due to access constraints, specialized care did not start until the child was 10 months old. Parents are consanguineous and were born in an area of high isonymy that is a cluster for rare recessive diseases. A new homozygous missense variant c.785G > T was found in exon 10 of the HSD17B3 gene. CONCLUSIONS: Researchers-clinicians and researchers-researchers collaborative efforts to elucidate the genetic basis of this disease were critical since this etiologic investigation is not available through the public health system. This case exemplifies the families' pilgrimage in cases of genital ambiguity due to a rare genetic condition. Recognizing the etiology was the baseline to provide information on prognosis and treatment options, and to shelter family and child doubts and hopes in order to better support their decisions.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Trastornos del Desarrollo Sexual , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/genética , Niño , Consanguinidad , Exones , Femenino , Humanos , Lactante , Masculino , Mutación Missense
3.
Rev. Bras. Saúde Mater. Infant. (Online) ; 20(2): 467-471, Apr.-June 2020. tab
Artículo en Inglés | Sec. Est. Saúde SP, LILACS | ID: biblio-1136441

RESUMEN

Abstract Objectives: the present study aimed to evaluate the association between the rs1799998 polymorphism of the CYP11B2 gene and the susceptibility to preeclampsia (PE) in a Brazilian population. Methods: the study group comprised 61 women who were diagnosed with PE. The control group included 116 women who did not show changes in their blood pressure levels during their pregnancies. The rs1799998 polymorphism of the CYP11B2 gene was amplified by allele-specific polymerase chain reaction (PCR). A multiple logistic regression analysis was performed using the SNPStat program to evaluate the risk of the CYP11B2 gene rs1799998 polymorphism contributing to PE. Results: the PE group had the following genotypes: 1.64% CC, 91.80% CT, and 6.56% TT. In the control group, the observed genotypic frequencies were: 11% CC, 73% CT, and 16% TT. The genotypic frequency distribution did not fit the Hardy Weinberg Equilibrium (HWE) in either study group. The multiple logistic regression analysis showed a statistically significant difference for the rs1799998 polymorphism in the recessive model. Conclusion: the results suggest an association between the recessive model of C/C genotype of the rs1799998 polymorphism of the CYP11B2 gene and susceptibility to PE.


Resumo Objetivos: avaliar a associação entre o polimorfismo rs1799998 do gene CYP11B2 e a suscetibilidade à PE em uma população brasileira. Métodos: participaram desse estudo 61 mulheres com PE e 116 mulheres normotensas. O polimorfismo rs1799998 do gene CYP11B2 foi amplificado por PCR alelo-específica. O risco do polimorfismo rs1799998 do gene CYP11B2 contribuir com a PE foi avaliado pela análise de regressão logística múltipla. Resultados: as frequências genotípicas observadas foram 1.64% CC, 91.80% CT e 6.56% TT no grupo PE e 11%CC, 73%CT e 16%TT grupo controle. A distribuição da frequência genotípica não estava em Equilíbrio de Hardy Weinberg em nenhum dos grupos estudados. A análise de regressão logística múltipla demonstrou diferença estatisticamente significativa para o polimorfismo rs1799998 no modelo recessivo. Conclusão: o presente trabalho sugere associação do genótipo C/C no modelo recessivo, do polimorfismo rs1799998 do gene CYP11B2 com a suscetibilidade a PE.


Asunto(s)
Humanos , Femenino , Embarazo , Polimorfismo Genético , Preeclampsia/genética , Citocromo P-450 CYP11B2 , Sistema Enzimático del Citocromo P-450 , Brasil , Marcadores Genéticos , Modelos Logísticos , Predisposición Genética a la Enfermedad , Perfil Genético
4.
Arch Gynecol Obstet ; 291(5): 1029-35, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25322977

RESUMEN

INTRODUCTION: Pre-eclampsia (PE) is a pregnancy-specific multisystemic syndrome characterized by high blood pressure and presence of protein in the urine. The pathogenesis of pre-eclampsia is poorly understood and many factors such as environment, genetic, and immunology may be involved in PE pathophysiology. Among the genetic factors, there is an association between pre-eclampsia and polymorphisms in some genes of different population samples, as vascular endothelial growth factor and interleukin 1 alpha. The vascular endothelial growth factor gene is highly polymorphic and acts as a regulator in endothelial cell proliferation and vascular permeability. The secretion of interleukin 1 alpha leads to a pro-inflammatory cascade, which leads to high levels of circulating cytokines. This high amount of cytokines corroborates to structural and functional alterations in endothelial cells. The aim of this study was to investigate the vascular endothelial growth factor (VEGF) G-634C and interleukin 1 alpha (IL1A) rs3783550 polymorphism in a specific Brazilian pre-eclampsia group. MATERIAL AND METHODS: The evaluation of the vascular endothelial growth factor polymorphism was performed by PCR-RFLP restriction enzyme BsmFI and the IL1A polymorphism by allele-specific PCR. Molecular investigation was carried out by fragment size analysis on agarose and/or polyacrylamide gels. RESULTS: However, no relation between polymorphism VEGF G-634C and pre-eclampsia was observed, indicating that further investigations with a larger sampling and other polymorphisms are still required. On the other hand, the rs3783550 polymorphism in the interleukin 1 alpha gene is correlated to pre-eclampsia, indicating that women with the allele A have a higher probability of developing the disease. CONCLUSION: Thus, the interleukin 1 alpha gene could be used as a therapeutic tool for the diagnosis, as well as for monitoring the patients.


Asunto(s)
Interleucina-1alfa/genética , Polimorfismo de Longitud del Fragmento de Restricción , Preeclampsia/genética , Factor A de Crecimiento Endotelial Vascular/genética , Adulto , Alelos , Brasil , Femenino , Humanos , Preeclampsia/metabolismo , Embarazo
5.
BMC Med Genet ; 15: 7, 2014 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-24405868

RESUMEN

BACKGROUND: Disorders of sex development (DSD) is the term used for congenital conditions in which development of chromosomal, gonadal, or phenotypic sex is atypical. Nuclear receptor subfamily 5, group A, member 1 gene (NR5A1) encodes steroidogenic factor 1 (SF1), a transcription factor that is involved in gonadal development and regulates adrenal steroidogenesis. Mutations in the NR5A1 gene may lead to different 46,XX or 46,XY DSD phenotypes with or without adrenal failure. We report a Brazilian family with a novel NR5A1 mutation causing ambiguous genitalia in 46,XY affected individuals without Müllerian derivatives and apparently normal Leydig function after birth and at puberty, respectively. Their mother, who is also heterozygous for the mutation, presents evidence of primary ovarian insufficiency. CASE PRESENTATION: Three siblings with 46,XY DSD, ambiguous genitalia and normal testosterone production were included in the study. Molecular analyses for AR, SRD5A2 genes did not reveal any mutation. However, NR5A2 sequence analysis indicated that all three siblings were heterozygous for the p.Cys65Tyr mutation which was inherited from their mother. In silico analysis was carried out to elucidate the role of the amino acid change on the protein function. After the mutation was identified, all sibs and the mother had been reevaluated. Basal hormone concentrations were normal except that ACTH levels were slightly elevated. After 1 mcg ACTH stimulation test, only the older sib showed subnormal cortisol response. CONCLUSION: The p.Cys65Tyr mutation located within the second zinc finger of DNA binding domain was considered deleterious upon analysis with predictive algorithms. The identification of heterozygous individuals with this novel mutation may bring additional knowledge on structural modifications that may influence NR5A1 DNA-binding ability, and may also contribute to genotype-phenotype correlations in DSD. The slightly elevated ACTH basal levels in all three patients with 46,XY DSD and the subnormal cortisol response after 1 mcg ACTH stimulation in the older sib indicate that a long-term follow-up for adrenal function is important for these patients. Our data reinforce that NR5A1 analysis must also be performed in 46,XY DSD patients with normal testosterone levels without AR mutations.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY/genética , Madres , Mutación , Insuficiencia Ovárica Primaria/genética , Hermanos , Factor Esteroidogénico 1/genética , Testosterona/metabolismo , Adolescente , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Niño , Femenino , Humanos , Lactante , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Factor Esteroidogénico 1/química
6.
Gene ; 523(1): 50-7, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23566828

RESUMEN

Mutations in the myocilin gene (MYOC) account for most cases of autosomal dominant juvenile-onset open-angle glaucoma (JOAG), an earlier and more severe form of POAG. We accessed seven members of a Brazilian JOAG family by clinical and molecular investigation. Four out of seven family members were diagnosed with JOAG. All of these patients presented high intraocular pressure and two of them were bilaterally blind. The disease onset varied from 20 to 30years old. There was a nine-year-old family member who had not yet manifested the disease, although he was also a carrier of the mutation. Ophthalmologic examination included: evaluation of the visual field and optic disc, intraocular pressure measurement, and gonioscopy. The three exons and intron/exon junctions of the MYOC gene were screened for mutations through direct sequencing of PCR-amplified DNA fragments. Mutation screening revealed an in-frame mutation in the third exon of the MYOC gene: an insertion of six nucleotides between the cDNA positions 1187 and 1188 (c.1187_1188insCCCAGA, p.D395_E396insDP). This mutation presented an autosomal dominant pattern of inheritance, segregating with the disease in four family members for three generations, and it was absent in 60 normal controls. We also performed a computational structure modeling of olfactomedin-like domain of myocilin protein and conducted in silico analysis to predict the structural changes in the myocilin protein due to the presence of the mutation. These findings may be important for future diagnosis of other presymptomatic family members, as well as for the increase of the panel of MYOC mutations and their effects on phenotype.


Asunto(s)
Proteínas del Citoesqueleto/genética , Proteínas del Ojo/genética , Glaucoma de Ángulo Abierto/genética , Glicoproteínas/genética , Mutación , Adulto , Edad de Inicio , Anciano , Secuencia de Aminoácidos , Brasil , Biología Computacional , Análisis Mutacional de ADN , Exones , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Glaucoma de Ángulo Abierto/diagnóstico , Gonioscopía , Humanos , Presión Intraocular/genética , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Oftalmología , Disco Óptico/patología , Linaje , Fenotipo , Estructura Terciaria de Proteína , Campos Visuales/genética , Adulto Joven
7.
Arq. bras. endocrinol. metab ; 56(8): 525-532, Nov. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-660261

RESUMEN

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.


Asunto(s)
Adolescente , Niño , Preescolar , Femenino , Humanos , Síndrome de Frasier/genética , Mutación/genética , Proteínas WT1/genética , Síndrome de Frasier/diagnóstico , Gonadoblastoma/genética , Neoplasias Ováricas/genética
8.
Arq Bras Endocrinol Metabol ; 56(8): 525-32, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23295293

RESUMEN

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.


Asunto(s)
Síndrome de Frasier/genética , Mutación/genética , Proteínas WT1/genética , Adolescente , Niño , Preescolar , Femenino , Síndrome de Frasier/diagnóstico , Gonadoblastoma/genética , Humanos , Neoplasias Ováricas/genética
9.
Int J Mol Sci ; 12(12): 9471-80, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22272144

RESUMEN

The steroid 5α-reductase type II enzyme catalyzes the conversion of testosterone (T) to dihydrotestosterone (DHT), and its deficiency leads to undervirilization in 46,XY individuals, due to an impairment of this conversion in genital tissues. Molecular analysis in the steroid 5α-reductase type II gene (SRD5A2) was performed in two 46,XY female siblings. SRD5A2 gene sequencing revealed that the patients were homozygous for p.Gln126Arg missense mutation, which results from the CGA > CAA nucleotide substitution. The molecular result confirmed clinical diagnosis of 46,XY disorder of sex development (DSD) for the older sister and directed the investigation to other family members. Studies on SRD5A2 protein structure showed severe changes at NADPH binding region indicating that structural modeling analysis can be useful to evaluate the deleterious role of a mutation as causing 5α-reductase type II enzyme deficiency.


Asunto(s)
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Proteínas de la Membrana/genética , Mutación Missense , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/química , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Adolescente , Secuencia de Aminoácidos , Sitios de Unión , Brasil , Niño , Trastorno del Desarrollo Sexual 46,XY/diagnóstico , Femenino , Homocigoto , Humanos , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Linaje
10.
Arq. bras. endocrinol. metab ; 54(8): 738-743, Nov. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-578349

RESUMEN

X-linked adrenoleukodystrophy (X-ALD) is an inherited disease with clinical heterogeneity varying from presymptomatic individuals to rapidly progressive cerebral ALD forms. This disease is characterized by increased concentration of very long chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues. Affected individuals can be classified in different clinical settings, according to phenotypic expression and age at onset of initial symptoms. Molecular defects in X-ALD individuals usually result from ABCD1 gene mutations. In the present report we describe clinical data and the ABCD1 gene study in two boys affected with the childhood cerebral form that presented with different symptomatic manifestations at diagnosis. In addition, their maternal grandfather had been diagnosed with Addison's disease indicating phenotypic variation for X-ALD within this family. The mutation p.Trp132Ter was identified in both male patients; additionally, three females, out of eleven family members, were found to be heterozygous after screening for this mutation. In the present report, the molecular analysis was especially important since one of the heterozygous females was in first stages of pregnancy. Therefore, depending on the fetus outcome, if male and p.Trp132Ter carrier, storage of the umbilical cord blood should be recommended as hematopoietic stem cell transplantation could be considered as an option for treatment in the future.


A adrenoleucodistrofia é uma doença genética com padrão de herança ligado ao X (X-ALD) que apresenta heterogeneidade clínica e varia desde a forma infantil cerebral severa até casos de indivíduos pré-sintomáticos. Essa doença é caracterizada pelo acúmulo de ácidos graxos de cadeia muito longa (VLCFA) no plasma, nas adrenais, nos testículos e no sistema nervoso. Indivíduos afetados podem apresentar diferentes formas clínicas, as quais são classificadas de acordo com a expressão fenotípica e a idade de aparecimento dos sintomas iniciais. Alterações moleculares em indivíduos com X-ALD são geralmente mutações no gene ABCD1. No presente trabalho, descrevemos os dados clínicos e a investigação molecular do gene ABCD1 em uma família com duas crianças do sexo masculino afetadas com a forma infantil cerebral, que apresentaram diferenças nas primeiras manifestações sintomáticas para o diagnóstico. Além disso, houve referência ao avô materno diagnosticado com doença de Addison's, indicando a variabilidade fenotípica da X-ALD nessa família. A análise molecular indicou a mutação p.Trp132Ter nos dois pacientes masculinos, e três indivíduos do sexo feminino, entre os onze estudados, mostraram-se heterozigotos para mutação. O conhecimento molecular descrito no presente relato adquiriu maior importância uma vez que uma das portadoras da mutação apresentou-se nos primeiros estágios de gestação. Assim, poderá ser oferecida a possibilidade de armazenamento de sangue de cordão umbilical para que se possa considerar, no futuro, o transplante de células-tronco hematopoiéticas como forma de tratamento, caso a criança seja do sexo masculino e afetada.


Asunto(s)
Niño , Femenino , Humanos , Masculino , Embarazo , Transportadoras de Casetes de Unión a ATP/genética , Adrenoleucodistrofia/genética , Linaje , Fenotipo , Mutación/genética , Análisis de Secuencia de ADN
11.
Arq. bras. endocrinol. metab ; 54(8): 754-760, Nov. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-578352

RESUMEN

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary cancer syndrome characterized mostly by parathyroid, enteropancreatic, and anterior pituitary tumors. We present a case of an 8-year-old boy referred because of hypoglycemic attacks. His diagnosis was pancreatic insulinoma. Paternal grandmother died due to repeated gastroduodenal ulcerations and a paternal aunt presented similar manifestations. At a first evaluation, the father presented only gastric ulceration but subsequently developed hyperparathyroidism and lung carcinoid tumor. During almost 15 years of follow-up, three brothers and the index case presented hyperparathyroidism and hyperprolactinemia. Molecular study showed a G to A substitution in intron 4, at nine nucleotides upstream of the splicing acceptor site, causing a splicing mutation. All affected members of the family have the same mutation. Paternal grandmother and aunt were not studied and the mother does not carry any mutation. MEN1 is a rare condition that requires permanent medical assistance. Early clinical and genetic identification of affected individuals is essential for their own surveillance and also for genetic counseling.


A neoplasia endócrina múltipla tipo 1 (NEM1) é uma doença hereditária autossômica dominante, caracterizada principalmente por tumores de paratireoide, enteropancreáticos e adeno-hipofisários. Apresentamos o caso de um menino com 8 anos encaminhado por crises de hipoglicemia. Seu diagnóstico foi insulinoma pancreático. Sua avó paterna faleceu por úlceras gastroduodenais de repetição e a tia paterna tinha as mesmas manifestações. Na primeira avaliação, o pai apresentou apenas úlcera gástrica, porém com a evolução desenvolveu hiperparatireoidismo e tumor carcinoide pulmonar. Durante cerca de 15 anos de seguimento, os três irmãos e o caso índice desenvolveram hiperparatireoidismo e hiperprolactinemia. O estudo molecular mostrou a substituição G por A no intron 4, a nove nucleotídeos do sítio aceptor de splicing, criando um novo sítio de splicing. Todos os membros da família afetados e estudados tinham a mesma mutação. A NEM1 é uma condição rara que requer assistência médica permanente. As identificações clínicas e genéticas precoces são essenciais para o tratamento e aconselhamento genético.


Asunto(s)
Niño , Humanos , Masculino , Insulinoma/genética , Neoplasia Endocrina Múltiple Tipo 1/genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas/genética , Intrones/genética , Mutación , Linaje
12.
Arq. bras. endocrinol. metab ; 54(8): 768-774, Nov. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-578354

RESUMEN

Type II 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase (3β-HSD2), encoded by the HSD3B2 gene, is a key enzyme involved in the biosynthesis of all the classes of steroid hormones. Deleterious mutations in the HSD3B2 gene cause the classical deficiency of 3β-HSD2, which is a rare autosomal recessive disease that leads to congenital adrenal hyperplasia (CAH). CAH is the most frequent cause of ambiguous genitalia and adrenal insufficiency in newborn infants with variable degrees of salt losing. Here we report the molecular and structural analysis of the HSD3B2 gene in a 46,XY child, who was born from consanguineous parents, and presented with ambiguous genitalia and salt losing. The patient carries a homozygous nucleotide c.665C>A change in exon 4 that putatively substitutes the proline at codon 222 for glutamine. Molecular homology modeling of normal and mutant 3β-HSD2 enzymes emphasizes codon 222 as an important residue for the folding pattern of the enzyme and validates a suitable model for analysis of new mutations.


A enzima 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase do tipo 2 (3β-HSD2), codificada pelo gene HSD3B2, é importante na biossíntese de todas as classes de hormônios esteroides. As mutações no gene HSD3B2 podem causar deficiência da 3β-HSD2 da forma clássica. É de herança autossômica recessiva e uma das causas mais raras de hiperplasia congênita da adrenal (HCA). A deficiência dessa enzima leva frequentemente à ambiguidade genital e à insuficiência da adrenal em recém-nascidos com vários níveis de perda de sal. Neste trabalho, foi feito o estudo estrutural e molecular do gene HSD3B2 gene em um paciente 46,XY, filho de pais consanguíneos, com ambiguidade genital e perda de sal. O paciente é homozigoto para a troca nucleotídica c.665C>A no éxon 4, que putativamente leva à substituição de uma prolina do códon 222 por uma glutamina. A modelagem molecular por homologia das enzimas 3β-HSD2 normal e mutantes ressaltou que a prolina no códon 222 é um resíduo importante no enovelamento da enzima e validou um modelo adequado para avaliações de novas mutações.


Asunto(s)
Humanos , Recién Nacido , Masculino , /deficiencia , Hiperplasia Suprarrenal Congénita/genética , Progesterona Reductasa/genética , /genética , Codón , Homocigoto , Mutación Missense
13.
J Pediatr Hematol Oncol ; 32(6): 486-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20562648

RESUMEN

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.


Asunto(s)
Síndrome de Denys-Drash/genética , Genes del Tumor de Wilms , Síndrome de Denys-Drash/complicaciones , Trastornos del Desarrollo Sexual/genética , Resultado Fatal , Humanos , Lactante , Recién Nacido , Neoplasias Renales/genética , Masculino , Mutación Puntual , Reacción en Cadena de la Polimerasa , Tumor de Wilms/genética
14.
Arq Bras Endocrinol Metabol ; 54(8): 738-43, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21340162

RESUMEN

X-linked adrenoleukodystrophy (X-ALD) is an inherited disease with clinical heterogeneity varying from presymptomatic individuals to rapidly progressive cerebral ALD forms. This disease is characterized by increased concentration of very long chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues. Affected individuals can be classified in different clinical settings, according to phenotypic expression and age at onset of initial symptoms. Molecular defects in X-ALD individuals usually result from ABCD1 gene mutations. In the present report we describe clinical data and the ABCD1 gene study in two boys affected with the childhood cerebral form that presented with different symptomatic manifestations at diagnosis. In addition, their maternal grandfather had been diagnosed with Addison's disease indicating phenotypic variation for X-ALD within this family. The mutation p.Trp132Ter was identified in both male patients; additionally, three females, out of eleven family members, were found to be heterozygous after screening for this mutation. In the present report, the molecular analysis was especially important since one of the heterozygous females was in first stages of pregnancy. Therefore, depending on the fetus outcome, if male and p.Trp132Ter carrier, storage of the umbilical cord blood should be recommended as hematopoietic stem cell transplantation could be considered as an option for treatment in the future.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Adrenoleucodistrofia/genética , Linaje , Fenotipo , Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP , Niño , Femenino , Humanos , Masculino , Mutación/genética , Embarazo/genética , Análisis de Secuencia de ADN
15.
Arq Bras Endocrinol Metabol ; 54(8): 754-60, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21340165

RESUMEN

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary cancer syndrome characterized mostly by parathyroid, enteropancreatic, and anterior pituitary tumors. We present a case of an 8-year-old boy referred because of hypoglycemic attacks. His diagnosis was pancreatic insulinoma. Paternal grandmother died due to repeated gastroduodenal ulcerations and a paternal aunt presented similar manifestations. At a first evaluation, the father presented only gastric ulceration but subsequently developed hyperparathyroidism and lung carcinoid tumor. During almost 15 years of follow-up, three brothers and the index case presented hyperparathyroidism and hyperprolactinemia. Molecular study showed a G to A substitution in intron 4, at nine nucleotides upstream of the splicing acceptor site, causing a splicing mutation. All affected members of the family have the same mutation. Paternal grandmother and aunt were not studied and the mother does not carry any mutation. MEN1 is a rare condition that requires permanent medical assistance. Early clinical and genetic identification of affected individuals is essential for their own surveillance and also for genetic counseling.


Asunto(s)
Insulinoma/genética , Neoplasia Endocrina Múltiple Tipo 1/genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas/genética , Niño , Humanos , Intrones/genética , Masculino , Mutación , Linaje
16.
Arq Bras Endocrinol Metabol ; 54(8): 768-74, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21340167

RESUMEN

Type II 3ß-hydroxysteroid dehydrogenase/Δ(5)-Δ(4)-isomerase (3ß-HSD2), encoded by the HSD3B2 gene, is a key enzyme involved in the biosynthesis of all the classes of steroid hormones. Deleterious mutations in the HSD3B2 gene cause the classical deficiency of 3ß-HSD2, which is a rare autosomal recessive disease that leads to congenital adrenal hyperplasia (CAH). CAH is the most frequent cause of ambiguous genitalia and adrenal insufficiency in newborn infants with variable degrees of salt losing. Here we report the molecular and structural analysis of the HSD3B2 gene in a 46,XY child, who was born from consanguineous parents, and presented with ambiguous genitalia and salt losing. The patient carries a homozygous nucleotide c.665C>A change in exon 4 that putatively substitutes the proline at codon 222 for glutamine. Molecular homology modeling of normal and mutant 3ß-HSD2 enzymes emphasizes codon 222 as an important residue for the folding pattern of the enzyme and validates a suitable model for analysis of new mutations.


Asunto(s)
3-Hidroxiesteroide Deshidrogenasas/deficiencia , Hiperplasia Suprarrenal Congénita/genética , Progesterona Reductasa/genética , 3-Hidroxiesteroide Deshidrogenasas/genética , Codón , Homocigoto , Humanos , Recién Nacido , Masculino , Mutación Missense
17.
Arq. bras. endocrinol. metab ; 52(8): 1221-1227, Nov. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-503287

RESUMEN

Morning glory syndrome (MGS) is a congenital optic disc dysplasia often associated with craniofacial anomalies, especially basal encephalocele and hypopituitarism. Clinical signs are varied and often occult. The PAX6 gene is involved in ocular morphogenesis and is expressed in numerous ocular tissues during development especially in the developing central nervous system. The aim of the present study is to evaluate PAX6 in MGS associated with isolated growth hormone deficiency. Three pre-pubertal males (A, B and C) with MGS and short stature due to growth hormone deficiency, treated with recombinant human growth hormone with limited response, were reported. Two of them had basal encephalocele. Coding and non-coding sequences corresponding of PAX6 different transcripts were analyzed by direct sequencing. Nucleotide variations causing putative aminoacid change were not observed. Patient A presented the new IVS2+9G>A transition, whereas patients A and C were heterozygous for known single nucleotide polymorphisms (SNP) within the intron 4. In addition, two SNP heterozygoses were observed for patient C in both intron 9 and 13. Sequencing also revealed several nucleotide variations in patient B. Two heterozygoses for known polymorphisms were identified along with a novel C>A nucleotide change in intron 4. This patient also presented a low number on the TG repeat in intron 9 and a new IVS11+33A>T transversion. Gene regulation and transcription of PAX6 are complex processes; there are two major protein isoforms, PAX6(-5a) and PAX6(+5a), and nine transcripts described. Furthermore, extra transcription regulatory elements have been postulated within PAX6 introns. Considering that neither population distributions on PAX6 polymorphism nor their linkeages with diseases have been reported, a functional effect due to alterations described here cannot be discarded.


A síndrome de Morning Glory (SMG) é uma displasia óptica congênita associada a anomalias craniofaciais, principalmente encefalocele basal e hipopituitarismo. Os sinais clínicos são variados e muitas vezes ocultos. O gene PAX6 está envolvido na morfogênese ocular e se expressa em vários tecidos oculares durante o desenvolvimento do sistema nervoso central. O objetivo deste estudo foi avaliar o gene PAX6 na SMG associada com deficiência isolada de hormônio de crescimento. Foram relatados três pacientes pré-púberes (A, B e C) com SMG e baixa estatura por deficiência de hormônio de crescimento tratados com hormônio de crescimento recombinante humano. As seqüências codificadoras e não-codificadoras correspondentes ao PAX6 em diferentes transcritos foram analisadas por seqüenciamento direto. Variações nucleotídeas com trocas pontuais de aminoácidos não foram encontradas. O paciente A apresentou uma transição nova IVS2+9G>A, enquanto os pacientes A e C foram heterozigotos para um polimorfismo (SNP) no íntron 4. Ainda, dois SNPs em heterozigose nos íntrons 9 e 13 foram observados no paciente C. O seqüenciamento também mostrou várias variações nucleotídeas no paciente B. Dois SNPs conhecidos com a alteração nucleotídea nova C>A no íntron 4 foram observados em heterozigose. Este paciente também apresentou um baixo número de repetições TG no íntron 9 e uma nova transversão IVS11+33A>T. A regulação e a transcrição do gene PAX6 são um processo complexo; existem 2 isoformas principais da proteína, PAX6(-5a) e PAX6(+5a) e 9 transcritos descritos. Considerando que nem a distribuição de SNPs no PAX6 e nem as suas ligações com as doenças foram relatadas, um defeito funcional devido às alterações descritas não pode ser descartado.


Asunto(s)
Niño , Humanos , Proteínas del Ojo/genética , Proteínas de Homeodominio/genética , Hormona de Crecimiento Humana/deficiencia , Mutación , Disco Óptico/anomalías , Enfermedades del Nervio Óptico/genética , Factores de Transcripción Paired Box/genética , Proteínas Represoras/genética , Secuencia de Bases , Encefalocele/diagnóstico , Heterocigoto , Hormona de Crecimiento Humana/uso terapéutico , Intrones/genética , Enfermedades del Nervio Óptico/congénito , Polimorfismo Genético , Análisis de Secuencia de ADN , Síndrome
18.
Arq. bras. endocrinol. metab ; 52(8): 1236-1243, Nov. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-503288

RESUMEN

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.


Asunto(s)
Adolescente , Niño , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Síndrome de Frasier , Genes del Tumor de Wilms , Neoplasias Renales , Proteínas WT1/genética , Amenorrea/diagnóstico , Resultado Fatal , Síndrome de Frasier/diagnóstico , Síndrome de Frasier/genética , Genitales/anomalías , Genitales/patología , Heterocigoto , Neoplasias Renales/diagnóstico , Neoplasias Renales/genética , Fenotipo , Insuficiencia Renal Crónica/diagnóstico
19.
Arq. bras. endocrinol. metab ; 52(8): 1244-1251, Nov. 2008. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-503289

RESUMEN

Mutations in the vitamin D receptor (VDR) are associated to the hereditary 1,25-dihydroxivitamin D-resistant rickets. The objectives of this work are: search for mutations in the VDR and analyze their functional consequences in four Brazilian children presented with rickets and alopecia. The coding region of the VDR was amplified by PCR e direct sequenced. We identified three mutations: two patients had the same mutation in exon 7 at aminoacid position 259 (p.Q259E); one patient had a mutation in exon 8 at codon 319 (p.G319V) and another one had a mutation in exon 3 leading to a truncated protein at position 73 (p.R73X). Functional studies of the mutant receptors of fibroblast primary culture, from patients' skin biopsy treated with increasing doses of 1,25(OH)2 vitamin D showed that VDR mutants were unable to be properly activated and presented a reduction in 24-hydroxylase expression level.


Mutações no receptor de vitamina D (VDR) são associadas a raquitismo hereditário resistente a 1,25-dihidroxivitamina D. Os objetivos deste trabalho foram procurar mutações no VDR e analisar suas conseqüências funcionais em quatro pacientes com raquitismo e alopécia. A região codificadora do VDR foi amplificada por PCR e seqüenciada diretamente. Identificamos três mutações: dois pacientes apresentavam a mesma mutação no éxon 7 na posição protéica 259 (p.Q259E); um paciente apresentava uma mutação no éxon 8 no códon 319 (p.G319V) e o outro apresentava uma mutação no exon 3 resultando em uma proteína truncada na posição 73 (p.R73X). O estudo funcional dos receptores mutados nos extratos de culturas de fibroblasto primárias obtidas de biópsia de pele dos pacientes, tratados com doses crescentes de 1,25(OH)2 vitamina D demonstraram que os receptores mutantes não apresentam ativação adequada apresentando expressão reduzida de 24-hidroxilase.


Asunto(s)
Niño , Femenino , Humanos , Masculino , Adulto Joven , Alopecia/genética , Raquitismo Hipofosfatémico Familiar/genética , Mutación , Receptores de Calcitriol/genética , Alopecia/tratamiento farmacológico , Secuencia de Bases , Calcitriol/uso terapéutico , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Raquitismo Hipofosfatémico Familiar/tratamiento farmacológico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Calcitriol/metabolismo , Análisis de Secuencia de ADN , Esteroide Hidroxilasas/genética , Esteroide Hidroxilasas/metabolismo , Vitaminas/uso terapéutico , Adulto Joven
20.
Arq. bras. endocrinol. metab ; 52(8): 1388-1392, Nov. 2008. ilus
Artículo en Inglés | LILACS | ID: lil-503310

RESUMEN

Steroid 21-hydroxylase deficiency (21-OHD) accounts for more than 90 percent of congenital adrenal hyperplasia. CAH newborn screening, in general, is based on 17-hydroxyprogesterone dosage (17-OHP), however it is complicated by the fact that healthy preterm infants have high levels of 17-OHP resulting in false positive cases. We report on molecular features of a boy born pre-term (GA = 30 weeks; weight = 1,390 g) with elevated levels of 17-OHP (91.2 nmol/L, normal < 40) upon neonatal screening who was treated as having CAH up to the age of 8 months. He was brought to us for molecular diagnosis. Medication was gradually suspended and serum 17-OHP dosages mantained normal. The p.V281L mutation was found in compound heterozygous status with a group of nucleotide alterations located at the 3' end intron 4 and 5' end exon 5 corresponding to the splice site acceptor region. Molecular studies continued in order to exclude the possibility of a nonclassical 21-OHD form. The group of three nucleotide changes was demonstrated to be a normal variant since they failed to interfere with the normal splicing process upon minigene studies.


A deficiência de 21-hidroxilase (21-OHD) é uma doença autossômica recessiva que contribui com mais de 90 por cento dos casos de hiperplasia congênita da adrenal. O teste de dosagem de 17-hidroxiprogesterona (17-OHP) por radioimunoensaio em amostras de sangue colhidas em papel de filtro tem sido o método mais usado nos programas de triagem neonatal. No entanto, essa triagem pode apresentar alto número de falso-positivos pelo fato de os recém-nascidos prematuros apresentarem dosagens mais elevadas deste esteróide. Apresentamos aqui os estudos moleculares de uma criança, sexo masculino, nascida pré-termo (IG = 30 sem; peso = 1.390 g) que apresentava valores elevados de 17-OHP sérica (91,2 nmol/L, normal < 40) na triagem neonatal e que foi tratada como portadora da forma clássica da 21-OHD até a idade de 8 meses quando nos foi encaminhada para diagnóstico molecular. A terapia foi, então, gradativamente descontinuada, sendo que as concentrações séricas de 17-OHP se mantiveram normais. A mutação p.V281L foi encontrada em heterozigose composta com um grupo de alterações no terminal 3' do íntron 4 e no terminal 5' do éxon 5 correspondendo à região do sítio aceptor de splicing. A análise do gene CYP21A2 prosseguiu para se excluir a possibilidade de a criança ser afetada com a forma não-clássica de 21-OHD. Pela análise de minigene ficou demonstrado que o grupo de três trocas nucleotídicas não afeta o processo normal de transcrição. Concluindo, a criança é apenas heterozigota da mutação p.V281L sem necessidade de tratamento.


Asunto(s)
Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Hiperplasia Suprarrenal Congénita/diagnóstico , Mutación/genética , Tamizaje Neonatal , /genética , /sangre , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/genética , Reacciones Falso Positivas , Heterocigoto , Nacimiento Prematuro
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