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2.
J Intern Med ; 279(1): 3-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26250718

RESUMO

Massively parallel DNA sequencing has revolutionized analyses of human genetic variation. From having been out of reach for individual research groups and even more so for clinical diagnostic laboratories until recently, it is now possible to analyse complete human genomes within reasonable time frames and at a reasonable cost using technologies that are becoming increasingly available. This represents a huge advance in our ability to provide correct diagnoses for patients with rare inherited disorders and their families. This paradigm shift is especially dramatic within the area of monogenic disorders. Not only can rapid and safe diagnostics of virtually all known single-gene defects now be established, but novel causes of disease in previously unsolved cases can also be identified, illuminating novel pathways important for normal physiology. This greatly increases the capability not only to improve management of rare disorders, but also to improve understanding of pathogenetic mechanisms relevant for common, complex diseases.


Assuntos
Doenças Genéticas Inatas/diagnóstico , Exoma , Frequência do Gene , Genômica , Humanos , Análise de Sequência de DNA
3.
Hum Reprod ; 29(8): 1818-27, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24939957

RESUMO

STUDY QUESTION: Can high-resolution array comparative genomic hybridization (CGH) analysis of DNA samples from women with primary ovarian insufficiency (POI) improve the diagnosis of the condition and identify novel candidate genes for POI? SUMMARY ANSWER: A mutation affecting the regulatory region of growth differentiation factor 9 (GDF9) was identified for the first time together with several novel candidate genes for POI. WHAT IS KNOWN ALREADY: Most patients with POI do not receive a molecular diagnosis despite a significant genetic component in the pathogenesis. STUDY DESIGN, SIZE, DURATION: We performed a case-control study. Twenty-six patients were analyzed by array CGH for identification of copy number variants. Novel changes were investigated in 95 controls and in a separate population of 28 additional patients with POI. The experimental procedures were performed during a 1-year period. PARTICIPANTS/MATERIALS, SETTING, METHODS: DNA samples from 26 patients with POI were analyzed by a customized 1M array-CGH platform with whole genome coverage and probe enrichment targeting 78 genes in sex development. By PCR amplification and sequencing, the breakpoint of an identified partial GDF9 gene duplication was characterized. A multiplex ligation-dependent probe amplification (MLPA) probe set for specific identification of deletions/duplications affecting GDF9 was developed. An MLPA probe set for the identification of additional cases or controls carrying novel candidate regions identified by array-CGH was developed. Sequencing of three candidate genes was performed. MAIN RESULTS AND THE ROLE OF CHANCE: Eleven unique copy number changes were identified in a total of 11 patients, including a tandem duplication of 475 bp, containing part of the GDF9 gene promoter region. The duplicated region contains three NOBOX-binding elements and an E-box, important for GDF9 gene regulation. This aberration is likely causative of POI. Fifty-four patients were investigated for copy number changes within GDF9, but no additional cases were found. Ten aberrations constituting novel candidate regions were detected, including a second DNAH6 deletion in a patient with POI. Other identified candidate genes were TSPYL6, SMARCC1, CSPG5 and ZFR2. LIMITATIONS, REASONS FOR CAUTION: This is a descriptive study and no functional experiments were performed. WIDER IMPLICATIONS OF THE FINDINGS: The study illustrates the importance of analyzing small copy number changes in addition to sequence alterations in the genetic investigation of patients with POI. Also, promoter regions should be included in the investigation. STUDY FUNDING/COMPETING INTERESTS: The study was supported by grants from the Swedish Research council (project no 12198 to A.W. and project no 20324 to A.L.H.), Stockholm County Council (E.I., A.W. and K.R.W.), Foundation Frimurare Barnhuset (A.N., A.W. and M.B.), Karolinska Institutet (A.N., A.L.H., E.I., A.W. and M.B.), Novo Nordic Foundation (A.W.) and Svenska Läkaresällskapet (M.B.). The funding sources had no involvement in the design or analysis of the study. The authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Variações do Número de Cópias de DNA , Duplicação Gênica , Fator 9 de Diferenciação de Crescimento/genética , Insuficiência Ovariana Primária/genética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Estudos de Coortes , Hibridização Genômica Comparativa/métodos , Feminino , Humanos
4.
Sex Dev ; 8(4): 146-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24481226

RESUMO

Ovarian dysfunction before the age of 40 years, characterized by hypergonadotropic hypogonadism and presenting with either primary or secondary amenorrhea, is called primary ovarian insufficiency (POI). POI has a significant genetic component, but the specific genetic cause is often unknown. A novel candidate gene for POI, PSMC3IP, has recently been identified. The aim of this study was to investigate a group of patients with POI for possible PSMC3IP mutations. Therefore, DNA samples from 50 patients with POI of primarily Swedish origin were used in the study, 27 with secondary amenorrhea (median age of diagnosis 23 years) and 23 with primary amenorrhea. Control material consisting of DNA samples from 95 women without POI was used for investigation of novel sequence variants. All exons and intron/exon boundaries of the PSMC3IP gene were analyzed by PCR and sequencing. As a result, no pathogenic mutation in the PSMC3IP gene was detected in the cohort. A previously unreported variant, NM_016556.3:c.337+33A>G, was detected in heterozygous form in 1 patient with secondary amenorrhea, likely constituting a normal variant. Two reported single nucleotide polymorphisms were detected in the cohort at the expected frequency. In conclusion, PSMC3IP gene mutations are not common causes of POI in this Swedish cohort.


Assuntos
Proteínas Nucleares/genética , Insuficiência Ovariana Primária/genética , Transativadores/genética , Adolescente , Adulto , Amenorreia/genética , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Insuficiência Ovariana Primária/epidemiologia , Suécia/epidemiologia , Adulto Jovem
5.
J Clin Endocrinol Metab ; 99(4): 1425-32, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24476073

RESUMO

CONTEXT: Congenital adrenal hyperplasia (CAH), CYP21A2 deficiency, results in cortisol and aldosterone deficiency and increased production of androgens, with a good genotype phenotype correlation. OBJECTIVE: The objective of the investigation was to study psychosocial outcomes in relation to clinical severity, CYP21A2 genotype, in men and women. DESIGN: This was an epidemiological study with a matched case control design. SETTING: The setting of the study was all known CAH patients in Sweden. PARTICIPANTS: Five hundred eighty-eight patients, more than 80% with known severity of CAH, and 100 controls per patient matched for sex, year, and place of birth participated in the study. MAIN OUTCOME AND MEASURES: Proxies for quality of life were selected: level of education, employment, income, sick leave, disability pension, marriage, and children. RESULTS: Women with salt-wasting (SW) CAH had completed primary education less often [odds ratio (OR) 0.3], not explained by neonatal salt crisis or hypoglycemia because the men did not differ from controls. Men and women in the less severe I172N genotype group were more likely to have an academic education (OR 1.8). SW women were more likely to have an income in the top 20th percentile (OR 2.0). Both men and women had more disability pension (OR 1.5) and sick leave (OR 1.7). The men more often had long-lasting employment (OR 3.1). Men were more often (OR 1.6) and women were less often married (OR 0.7). Patients had children less often (OR 0.3). CONCLUSIONS: This study shows important outcome differences regarding education; employment; marriage and fertility, depending on sex; and severity of CAH. The mechanisms behind this and the increased risk for sick leave or disability pension in both men and women should be identified to improve medical and psychological care.


Assuntos
Hiperplasia Suprarrenal Congênita/epidemiologia , Hiperplasia Suprarrenal Congênita/psicologia , Adolescente , Hiperplasia Suprarrenal Congênita/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Psicologia , Qualidade de Vida/psicologia , Índice de Gravidade de Doença , Esteroide 21-Hidroxilase/genética , Suécia/epidemiologia , Adulto Jovem
6.
Eur J Endocrinol ; 166(2): 341-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22080441

RESUMO

OBJECTIVE: Most patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth. DESIGN AND METHODS: Clinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function. RESULTS: LH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenotype. In the girl, gonadectomy at 13 years revealed incomplete spermatogenesis and bilateral precursor lesions of testicular carcinoma in situ. In the boy, at the age of 12, numerous germ cells without signs of malignancy were present in bilateral testicular biopsy specimen. CONCLUSIONS: In SF-1 mutations, the neonatal phenotype poorly predicts virilization at puberty. Even in poorly virilized cases at birth, male gender assignment may allow spontaneous puberty without signs of hypogonadotropic hypogonadism, and possibly fertility. Patients with SF-1 mutations are at increased risk for malignant germ cell tumors. In case of preserved gonads, early orchidopexy and germ cell tumor screening is warranted. The finding of premalignant and/or malignant changes should prompt gonadectomy or possibly irradiation.


Assuntos
Disgenesia Gonadal 46 XY/genética , Gônadas/patologia , Parto/fisiologia , Fator Esteroidogênico 1/genética , Virilismo/genética , Virilismo/patologia , Adolescente , Sequência de Bases , Feminino , Disgenesia Gonadal 46 XY/patologia , Humanos , Recém-Nascido , Masculino , Mutação/fisiologia , Fenótipo , Puberdade/genética , Puberdade/fisiologia
7.
J Endocrinol Invest ; 35(3): 298-305, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21521936

RESUMO

BACKGROUND: Congenital adrenal hyperplasia (CAH) is mainly caused by the deficiency of the 21-hydroxylase enzyme coded by the CYP21A2 gene. However, some alleles in the non-classical form (NC-CAH) remain without identified mutations, suggesting the involvement of regulatory regions. AIM: Our objective was to study an allele carrying the variant *13 G>A in the 3'UTR of the CYP21A2 gene identified in some patients with a mild form of NC-CAH in order to verify the possible implication of this variation with the phenotype observed. SUBJECTS AND METHODS: Among all the subjects in whom the CYP21A2 gene was analyzed, 14 patients and 7 relatives heterozygous or homozygous for the *13 G>A substitution in 3'UTR were selected. Sequencing of DNA, genotyping, multiplex ligation-dependent probe amplification (MLPA), in vitro studies and bioinformatic analysis were performed. RESULTS: The haplotype of the *13 G>A allele was identical in all the subjects with a monomodular structure composed by one C4A gene and one CYP21A2 gene without a second module with the CYP21A1P pseudogene. No other concomitant mutations were found in the region extending from 3 kb in the promoter and encompassing the polyadenylation signal. Both bioinformatic analysis and in vitro studies predicted an alteration of the RNA folding and expression, but no miRNA target sequences were found in this region. CONCLUSIONS: The identification of a substitution in the 3'UTR of the gene associated with a mild form of NC-CAH suggests the importance of analyzing the CYP21A2 untranslated regions to better characterize and treat this subgroup of patients.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Esteroide 21-Hidroxilase/genética , Regiões 3' não Traduzidas/genética , Adolescente , Hiperplasia Suprarrenal Congênita/diagnóstico , Adulto , Criança , Feminino , Predisposição Genética para Doença/genética , Variação Genética , Haplótipos , Humanos , Masculino , Modelos Genéticos , Conformação de Ácido Nucleico , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/química , RNA Mensageiro/genética , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
8.
Sex Dev ; 5(4): 181-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21654157

RESUMO

Steroidogenic factor 1 (SF1, officially NR5A1) is a nuclear receptor involved in adrenal and gonadal development. NR5A1 mutations have been identified in patients with various forms of 46,XY disorders of sex development (DSD), including complete gonadal dysgenesis with or without adrenal insufficiency, mild testicular dysgenesis with ambiguous external genitalia or female external genitalia with clitoromegaly, and penoscrotal hypospadias. We developed a synthetic probe set for MLPA analysis of the NR5A1 gene covering its 7 exons and analyzed 20 patients with 46,XY gonadal DSD in whom analyses failed to identify a genetic cause. We identified a partial NR5A1 deletion affecting exons 2 and 3, leading to NR5A1 haploinsufficiency in 1 patient presenting with female external genitalia with clitoromegaly, absence of a uterus, and mildly dysgenetic testes. This is the first partial NR5A1 gene deletion identified by MLPA in a patient with 46,XY gonadal DSD. This finding stresses the importance of investigating copy number changes, even at the exon level, in genes involved in gonadal DSD. As NR5A1 mutations can cause a wide spectrum of DSD with relatively high frequency, the analysis of the NR5A1 gene by MLPA is quite important and should be extended to larger groups of patients.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual/genética , Deleção de Genes , Técnicas de Sonda Molecular , Fator Esteroidogênico 1/genética , Humanos , Masculino , Sondas Moleculares , Reação em Cadeia da Polimerase
9.
Semin Fetal Neonatal Med ; 16(2): 119-27, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21303737

RESUMO

Infants born with ambiguous genitalia represent a complex clinical challenge. A systematic clinical investigation aims at determining the hormone production and which anatomical structures are present in order to understand at what level the sex differentiation has been affected; chromosomal, gonadal or hormonal synthesis and action levels. The increased genetic knowledge in the field has opened up new diagnostic possibilities. Sex development requires the balanced and sequential activation of transcription factors, signaling molecules and hormones. It has recently been shown that not only testis but also normal ovarian development is an active process. Genes involved in gonadal disorders of sex development often act in a gene dosage-dependent manner, with different effects in XY or XX embryos. The management of patients with disorders of sex development, including decisions about sex of rearing, must be carried out by a specialized multidisciplinary team and include an extended genetic investigation as well as psychological considerations.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Diferenciação Sexual/genética , Transtornos do Desenvolvimento Sexual/diagnóstico , Feminino , Humanos , Recém-Nascido , Masculino
10.
Clin Genet ; 73(5): 453-64, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18384427

RESUMO

The development of a testis requires the proper spatiotemporal expression of the SRY gene and other genes that act in a dosage-sensitive manner. Mutations in the SRY gene account for only 10-15% of patients with 46,XY gonadal disorder of sex development (DSD). To enable the diagnostics of deletions and duplications of genes known to be involved in different forms of DSD, we developed a synthetic probe set for multiplex ligation-dependent probe amplification (MLPA) analysis. Here, we report the results from the analysis of 22 patients with 46,XY gonadal DSD. The analysis with the DSD probe set has led to the identification of two copy number variations, an 800-kb NR0B1 (DAX1) locus duplication on Xp21 in a patient with isolated partial gonadal dysgenesis and a duplication of the SRD5A2 gene that represents a rare normal variant. The described MLPA kit represents an optimal complement to DNA sequence analysis in patients with DSD, enabling screening for deletions and duplications of several genes simultaneously. Furthermore, the second identification of an NR0B1 locus duplication in a patient with isolated gonadal dysgenesis, without dysmorphic features and/or mental retardation, highlights the importance of evaluating NR0B1 duplication in patients with gonadal dysgenesis.


Assuntos
Proteínas de Ligação a DNA/análise , Dosagem de Genes , Disgenesia Gonadal 46 XY/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Receptores do Ácido Retinoico/análise , Proteínas Repressoras/análise , Receptor Nuclear Órfão DAX-1 , Proteínas de Ligação a DNA/genética , Feminino , Amplificação de Genes , Duplicação Gênica , Humanos , Masculino , Sondas de Oligonucleotídeos , Receptores do Ácido Retinoico/genética , Proteínas Repressoras/genética
11.
J Clin Endocrinol Metab ; 93(6): 2416-20, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18381579

RESUMO

BACKGROUND: Most patients with 21-hydroxylase deficiency carry CYP21A1P-derived mutations, but an increasing number of novel and rare mutations have been reported in disease-causing alleles. OBJECTIVE: Functional effects of three novel (p.G56R, p.L107R, p.L142P) and one recurrent (p.R408C) CYP21A2 mutations were investigated. The degree of enzyme impairment caused by p.H62L alone or combined to p.P453S was also analyzed. DESIGN: The study included 10 Brazilian and two Scandinavian patients. To determine the deleterious role of each mutant protein, in vitro assays were performed in transiently transfected COS-1 cells. For a correct genotype-phenotype correlation, the enzymatic activities were evaluated toward the two natural substrates, 17-hydroxyprogesterone and progesterone. RESULTS: Low levels of residual activities obtained for p.G56R, p.L107R, p.L142P, and p.R408C mutants classified them as classical congenital adrenal hyperplasia mutations, whereas the p.H62L showed an activity within the range of nonclassical mutations. Apparent kinetic constants for p.H62L confirmed the nonclassical classification as the substrate binding capacity was within the same magnitude for mutant and normal enzymes. A synergistic effect was observed for the allele bearing the p.H62L+p.P453S combination because it caused a significant reduction in the enzymatic activity. CONCLUSIONS: We describe the functional analysis of five rare missense mutations identified in Brazilian and Scandinavian patients. The p.G56R, p.L107R, and p.L142P are reported for the first time. Most probably these novel mutations are closer to null than the p.I172N, but for the p.G56R, that might not be the case, and the p.H62L is definitely a nonclassical mutation.


Assuntos
Mutação de Sentido Incorreto , Esteroide 21-Hidroxilase/genética , Animais , Brasil , Células COS , Criança , Pré-Escolar , Chlorocebus aethiops , Ativação Enzimática/genética , Feminino , Testes Genéticos , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Mutação de Sentido Incorreto/fisiologia , Países Escandinavos e Nórdicos , Esteroide 21-Hidroxilase/metabolismo , Esteroide 21-Hidroxilase/fisiologia , Transfecção
12.
Sex Dev ; 1(6): 363-72, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18391548

RESUMO

Testatin has been implicated in fetal testis development due to its restricted expression in pre-Sertoli cells immediately after the onset of Sry gene expression. However, testatin knockout mice showed normal testis development and fertility. We investigated the spatial and temporal expression pattern of the Cres/testatin subgroup of genes, including the novel gene Cstl1/Cres4, in fetal mouse gonads and in adult testis, epididymis and ovary. The genes are related to the family 2 cystatins of protease inhibitors. Using real-time PCR and in situ hybridization we could show that 4 subgroup genes, testatin, CstSC, CstTE-1/Cres3 and Cres are expressed in fetal testis. We also confirmed the expression of testatin, CstE2, CstSC, CstTE-1/Cres3, Cres, CstT and Cstl1/Cres4 in adult testis and CstE2, CstTE-1/Cres3, Cres and CstE1/Cres2 in adult epididymis. In testatin knockout animals, the expression of CstE2 was heavily downregulated in adult testis, but not in adult epididymis, compared to wildtype controls. In conclusion, an explanation for the lack of phenotype in testatin knockout mice could be functional redundancy with another member of the Cres/testatin subgroup. The most likely candidate/s would be CstSC, CstTE-1/Cres3 or Cres as they are expressed in the fetal testicular tubules in early testis differentiation together with testatin.


Assuntos
Cistatinas/genética , Expressão Gênica , Reprodução/genética , Testículo/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Cistatinas/química , Cistatinas/deficiência , Epididimo/química , Feminino , Hibridização In Situ , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Ovário/química , Ovário/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Testículo/química , Testículo/embriologia
13.
J Mol Med (Berl) ; 84(6): 521-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16541276

RESUMO

Congenital adrenal hyperplasia (CAH) is most commonly due to 21-hydroxylase deficiency and presents with a wide spectrum of clinical manifestations, from prenatal virilization and salt-wasting in the neonatal period to precocious pubarche and late-onset hyperandrogenic symptoms during adulthood. A limited number of mutations account for the majority of all mutated alleles, but a growing number of rare mutations are responsible for the disease in some patients. By sequence analysis of the CYP21A2 gene, we identified two novel (I171N and L446P) and two rare (R341P and R426H) mutations in seven Italian patients with CAH. One of the patients was diagnosed with mild non-classical CAH and was found to be a compound heterozygote (I171N/V281L), while all other patients showed severe phenotypes with latent or manifest salt-wasting. The residual activities measured after expression of the four mutant enzymes in COS-1 cells were all below 1% towards both natural substrates (17-OH-progesterone and progesterone) compared with the wild-type protein. All four mutations are, thus, associated with severe enzyme deficiency and are predicted to cause classic CAH if found in trans with other mutations causing severe enzyme deficiency.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Mutação , Esteroide 21-Hidroxilase/genética , 17-alfa-Hidroxiprogesterona/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Criança , Pré-Escolar , Chlorocebus aethiops , Feminino , Ligação Genética , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Progesterona/metabolismo , Homologia de Sequência de Aminoácidos , Esteroide 21-Hidroxilase/metabolismo , Especificidade por Substrato
14.
J Clin Endocrinol Metab ; 89(5): 2402-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15126570

RESUMO

Congenital adrenal hyperplasia (CAH) is most commonly due to 21-hydroxylase deficiency and presents a wide spectrum of clinical manifestations from a severe classical form to a milder late-onset form with a variable severity of hyperandrogenic symptoms. A limited number of mutations account for the majority of the mutated alleles, but additional rare mutations are responsible for the symptoms in some patients. By CYP21 gene analysis, we identified a chimeric CYP21P/CYP21 gene with the fusion breakpoint downstream of the common P30L mutation as well as a GCC to ACC change at codon 15 (A15T) in two subjects with classical CAH and a CCC to TCC change at codon 482 (P482S) in seven subjects referred for nonclassical CAH, precocious pubarche, menstrual irregularities, or hypertrichosis. The two amino acid substitutions were reconstructed by in vitro site-directed mutagenesis, the proteins were transiently expressed in COS-1 cells, and enzyme activity toward the two natural substrates (17-hydroxyprogesterone and progesterone) was determined. The A15T mutant exhibited no significant difference in activity compared with the wild-type protein, whereas the P482S mutation reduced enzyme activity to 70% of normal. This impairment of activity was confirmed in vivo by detection of heterozygote carriers by the ACTH test.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Esteroide 21-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/enzimologia , Substituição de Aminoácidos , Animais , Células COS , Criança , Pré-Escolar , Chlorocebus aethiops , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Leucina/genética , Masculino , Prolina/genética , Serina/genética , Esteroide 21-Hidroxilase/metabolismo
15.
J Mol Med (Berl) ; 79(10): 581-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11692155

RESUMO

We studied the functional and structural effects of two unique missense mutations in CYP21 found in patients with simple virilizing congenital adrenal hyperplasia. The rare variants L300F and V281G were found in two girls who were each hemizygous for one of the mutations. Functional analysis after expression in COS-1 cells revealed that the mutant enzymes had reduced enzymatic activity for conversion of both 17-hydroxyprogesterone (L300F 9.5%, V281G 3.9% of normal) and progesterone (L300F 4.4%, V281G 3.9% of normal). Both mutant enzymes had an increased degradation in mammalian COS-1 cells compared to the normal protein, although the L300F variant affected the degradation pattern to a greater extent. Our data indicate that the residue L300 is important in maintaining normal structure of the 21-hydroxylase enzyme whereas mutations affecting V281 most likely cause impaired enzyme activity by interfering with a specific function(s) of the protein.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Esteroide 21-Hidroxilase/genética , Virilismo/genética , 17-alfa-Hidroxiprogesterona/metabolismo , Adolescente , Hiperplasia Suprarrenal Congênita/enzimologia , Adulto , Sequência de Aminoácidos , Animais , Células COS , DNA/química , DNA/genética , Análise Mutacional de DNA , Feminino , Vetores Genéticos/genética , Humanos , Cinética , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Progesterona/metabolismo , Homologia de Sequência de Aminoácidos , Esteroide 21-Hidroxilase/metabolismo , Especificidade por Substrato , Transfecção , Virilismo/enzimologia
16.
Pediatrics ; 108(4): E68, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11581476

RESUMO

OBJECTIVE: Neonatal screening for congenital adrenal hyperplasia (CAH) among preterm infants is complicated by the fact that healthy preterm infants have higher levels of 17-hydroxyprogesterone (17-OHP) than term infants, resulting in a higher false-positive rate. Even when gestational age-related cutoff levels after ether extraction were used, the false-positive cases primarily comprised preterm infants. The aim of the study was to optimize the procedure for neonatal screening for CAH in preterm infants. METHODS: The 17-OHP levels in 6200 preterm infants were correlated to the gestational age. We also calculated the number of recalls for different putative cutoff levels of the 17-OHP by direct assay and after extraction in 1275 preterm infants who represented the most elevated cases in a population of approximately 30 000 preterm infants. The CYP21 genotypes and screening levels were determined in the 12 preterm infants with CAH diagnosed since the start of screening. The effect of possible interfering factors such as gestational age, neonatal stress, and prenatal glucocorticoid treatment for pulmonary maturation was studied. RESULTS: The extraction procedure did not significantly improve the sensitivity or specificity of the screening, whereas it delayed the day of recall from 8 to 13 days (median). We could not demonstrate any systematic influence of the studied stress factors or the prenatal glucocorticoid treatment on the 17-OHP screening levels. In the patients with CAH, the 17-OHP levels correlated better with disease severity than with the degree of prematurity. CONCLUSIONS: On the basis of these results, we omitted the extraction step and changed the cutoff levels in the Swedish screening program for preterm infants. We chose to use a cutoff level of 400 nmol/L plasma in infants who were born before week 35 and 150 nmol/L for infants who were born in weeks 35 and 36. For detecting more patients, the cutoff level would have to be much lower, which would result in a number of false-positive tests that we consider to be unacceptably high. It is clear that neonatal screening cannot detect all infants with CAH. Some milder forms of the disease, just like in the past, will have to be diagnosed on the basis of clinical signs and symptoms.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Hiperplasia Suprarrenal Congênita/diagnóstico , Doenças do Prematuro/diagnóstico , Mutação , Triagem Neonatal/métodos , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/genética , Deleção de Genes , Genótipo , Humanos , Recém-Nascido , Doenças do Prematuro/sangue , Doenças do Prematuro/genética , Radioimunoensaio
17.
World J Surg ; 25(7): 957-66, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11572038

RESUMO

Adenomas of the adrenal cortex cause different disorders depending on the main steroid synthesized and released. The aim of this research is to increase our understanding of the pathophysiology of steroidogenesis in adrenocortical disorders by comparing the release of steroids from adrenocortical adenomas in vitro with the messenger RNA (mRNA) expression of steroid synthesizing enzymes. Fourteen patients with adrenal tumors were included in the present study; nine were diagnosed with primary aldosteronism and three with Cushing's syndrome. Two patients had an adrenal tumor discovered on computed tomography (CT) during workup for an unrelated disease. Serum cortisol, plasma aldosterone, and urinary catecholamines were normal. Tissue was taken for in vitro steroid release, and aldosterone and cortisol in the medium after a 1-hour incubation were determined. Oligonucleotide probes with sequences complementary to mRNAs encoding for the steroid synthesizing enzymes 11 beta-hydroxylase (CYP11B1), 18-hydroxylase (CYP11B2), 17 alpha-hydroxylase (CYP17), and 21-hydroxylase (CYP21) were synthesized (Genset, Paris, France) and in situ hybridization was performed. Moderate expression of CYP11B2 and low expression of CYP11B1 were seen in the zona glomerulosa. The zona fasciculata of the control adrenals expressed a high signal of CYP11B1, whereas the expression of CYP11B2 was very low. There was considerable variation in aldosterone release from the aldosteronomas, whereas the tumors from the Cushing patients showed no detectable release of aldosterone. In contrast, tumors from patients with primary aldosteronism, Cushing's syndrome, and no hyperfunction all had the ability to synthesize and release cortisol in vitro. The highest cortisol release was found in tumors from patients with Cushing's syndrome, but also the nonhyperfunctioning tumors and some of the aldosteronomas released significant amounts of cortisol. The two patients with highest release of aldosterone in vitro showed the highest expression of CYP11B2 and the lowest expression of CYP11B1 and CYP17. The remaining aldosteronomas had low expression of CYP11B2, similar to the two other groups. Expression of CYP11B1 was high as expected in the Cushing adenomas, but also the two nonhyperfunctioning tumors and some of the aldosteronomas showed a moderate expression. Adenomas from Cushing's syndrome, nonhyperfunctioning adenomas, and some of the aldosterone-producing adenomas had moderate to high expression of CYP17. This paper presents new means for functional characterization of adrenocortical tumors. Diagnosis of an aldosteronoma is often difficult, and with the advent of these methods it is possible to determine the functional capacity of a tumor, once it is removed. This is of special interest if the patient remains hypertensive postoperatively, and it is not clear whether the patient indeed had a functioning tumor.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/metabolismo , Adenoma Adrenocortical/genética , Adenoma Adrenocortical/metabolismo , Aldosterona/análise , Citocromo P-450 CYP11B2/genética , Hidrocortisona/análise , RNA Mensageiro/genética , Esteroide 17-alfa-Hidroxilase/genética , Neoplasias do Córtex Suprarrenal/enzimologia , Adenoma Adrenocortical/enzimologia , Adulto , Idoso , Síndrome de Cushing/enzimologia , Síndrome de Cushing/genética , Feminino , Humanos , Hiperaldosteronismo/enzimologia , Hiperaldosteronismo/genética , Hibridização In Situ , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Técnicas de Sonda Molecular , Esteroide 11-beta-Hidroxilase/genética
18.
Clin Endocrinol (Oxf) ; 54(6): 827-34, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422119

RESUMO

OBJECTIVE: Resistance to androgens has been suggested as a possible cause of male infertility. This hypothesis is based mainly on binding studies in genital skin fibroblasts but the molecular evidence is sparse. DESIGN: Molecular studies of the androgen receptor gene were performed in 10 azoo- or oligozoospermic men, presenting with clinical signs of low androgen activity-poor virilization and high serum LH despite elevated testosterone levels, but without genital malformations. PATIENTS: Ten men with serum LH >10 IU/l and testosterone >30 nmol/l as well as a low sperm concentration < 20 x 106/ml. MEASUREMENTS: Genomic DNA was prepared from peripheral leucocytes and PCR-amplification of the coding region of androgen receptor was performed, followed by direct sequencing. Identified mutations were reconstructed by site-directed mutagenesis and the functional properties of the mutants were analysed, using transient expression in COS-1 cells and subsequent transactivation assays. Hormone binding assays were performed in genital skin fibroblasts from the patients. RESULTS: Two of the 10 men were shown to have a mutation in the androgen receptor gene. Subject 1, who presented with azoospermia, serum testosterone (T) 50 nmol/l and LH 20 IU/l, had a mutation in exon 1, changing amino acid asparagine 233 to lysine (N233K). In fibroblasts cultured from genital skin, the receptor affinity for 5alpha-dihydrotestosterone (DHT) was normal as compared to healthy controls, but the receptor-hormone complex was thermolabile at 42 degrees C. Subject 2 exhibited severe oligozoospermia and a similar endocrine pattern (T = 50 nmol/l and LH = 25 IU/l). He had a mutation in exon 5 changing asparagine 756 to serine (N756S). The affinity for DHT in cultured genital fibroblasts from this patient was reduced. Transactivation was abnormal for both mutants, N233K reaching 46% and N756S 38% of wild type activity when stimulated with 10 nmol/l DHT. CONCLUSIONS: Androgen receptor mutations may affect sperm production without resulting in genital malformations. Thus, in infertile men with a clinical presentation of poor androgen activity and an endocrine profile compatible with androgen resistance, mutations in the androgen receptor should be taken into consideration.


Assuntos
Infertilidade Masculina/genética , Mutação Puntual , Receptores Androgênicos/genética , Animais , Western Blotting , Células COS , Células Cultivadas , Di-Hidrotestosterona/metabolismo , Fibroblastos/metabolismo , Hormônio Foliculoestimulante/sangue , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/patologia , Hormônio Luteinizante/sangue , Masculino , Mutagênese Sítio-Dirigida , Ligação Proteica , Receptores Androgênicos/metabolismo , Globulina de Ligação a Hormônio Sexual/análise , Contagem de Espermatozoides , Testosterona/sangue , Transfecção
19.
Horm Res ; 53(2): 83-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10971094

RESUMO

The androgen insensitivity syndrome is a disorder caused by deficient function of the androgen receptor, characterized by varying degrees of undermasculinization in karyotypic males. We have identified four mutations in the androgen receptor gene, in the region encoding the DNA-binding domain of the protein. Two mutations, R607X and R615G, were found in patients with complete insensitivity to androgens, whereas the other two, S578T and A596T, were found in patients with partial insensitivity. The functional consequences of the three missense mutations were assayed in vitro after transient expression of the receptors in COS cells. All mutants showed normal androgen binding but abnormal abilities to stimulate transcription of an androgen-responsive reporter gene. R615G abolished transactivation whereas S578T and A596T were partially malfunctional. The function of A596T, but not of S578T, was normalized at high androgen concentrations in vitro, reflecting the in vivo situation. Thus, patients with specific mutations in the DNA-binding domain of the androgen receptor may benefit from androgen treatment.


Assuntos
Síndrome de Resistência a Andrógenos/tratamento farmacológico , Síndrome de Resistência a Andrógenos/genética , DNA/metabolismo , Mutação , Receptores Androgênicos/genética , Testosterona/uso terapêutico , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Células COS , Éxons , Humanos , Masculino , Metribolona/metabolismo , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Testosterona/administração & dosagem , Congêneres da Testosterona/metabolismo , Ativação Transcricional , Transfecção
20.
Psychol Rep ; 86(3 Pt 2): 1201-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10932580

RESUMO

ABC Relaxation Theory proposes 15 psychological relaxation-related states (R-States): Sleepiness, Disengagement, Physical Relaxation, Mental Quiet, Rested/Refreshed, At Ease/At Peace, Energized, Aware, Joy, Thankfulness and Love, Prayerfulness, Childlike Innocence, Awe and Wonder, Mystery, and Timeless/Boundless/Infinite. The present study summarizes the results of 13 separate factor analyses of immediate relaxation-related states, states associated with recalled relaxation activities, relaxation dispositions, and relaxation motivations on a combined sample of 1,904 individuals (group average ages ranged from 28-40 yr.). Four exploratory factor analyses of Smith Relaxation Inventories yielded 15 items that most consistently and exclusively load (generally at least .70) on six replicated factors. These items included happy, joyful, energized, rested, at peace, warm, limp, silent, quiet, dozing, drowsy, prayerful, mystery, distant, and indifferent. Subsequent factor analyses restricted to these items and specifying six factors were performed on 13 different data sets. Each yielded the same six-factor solution: Factor 1: Centered Positive Affect, Factor 2: Sleepiness, Factor 3: Disengagement, Factor 4: Physical Relaxation, Factor 5: Mental Quiet, and Factor 6: Spiritual. Implications for ABC Relaxation Theory are discussed.


Assuntos
Rememoração Mental , Motivação , Inventário de Personalidade/estatística & dados numéricos , Terapia de Relaxamento , Adulto , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes
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