Mutations Of Androgen Receptor Gene In Brazilian Patients With Male Pseudohermaphroditism.

We describe the identification of point mutations in the androgen receptor gene in five Brazilian patients with female assignment and behavior. The eight exons of the gene were amplified by the polymerase chain reaction (PCR) and analyzed for single-strand conformation polymorphism (SSCP) to detect the mutations. Direct sequencing of the mutant PCR products demonstrated single transitions in three of these cases: G-->A in case 1, within exon C, changing codon 615 from Arg to His; G-->A in case 2, within exon E, changing codon 752 from Arg to Gln, and C-->T in case 3, within exon B, but without amino acid change.31775-

Mutations In Sry And Wt1 Genes Required For Gonadal Development Are Not Responsible For Xy Partial Gonadal Dysgenesis.

The WT1 transcription factor regulates SRY expression during the initial steps of the sex determination process in humans, activating a gene cascade leading to testis differentiation. In addition to causing Wilms' tumor, mutations in WT1 are often responsible for urogenital defects in men, while SRY mutations are mainly related to 46,XY pure gonadal dysgenesis. In order to evaluate their role in abnormal testicular organogenesis, we screened for SRY and WT1 gene mutations in 10 children with XY partial gonadal dysgenesis, 2 of whom with a history of Wilms' tumor. The open reading frame and 360 bp of the 5' flanking sequence of the SRY gene, and the ten exons and intron boundaries of the WT1 gene were amplified by PCR of genomic DNA. Single-strand conformation polymorphism was initially used for WT1 mutation screening. Since shifts in fragment migration were only observed for intron/exon 4, the ten WT1 exons from all patients were sequenced manually. No mutations were detected in the SRY 5' untranslated region or within SRY open-reading frame sequences. WT1 sequencing revealed one missense mutation (D396N) in the ninth exon of a patient who also had Wilms' tumor. In addition, two silent point mutations were found in the first exon including one described here for the first time. Some non-coding sequence variations were detected, representing one new (IVS4+85A>G) and two already described (-7ATG T>G, IVS9-49 T>C) single nucleotide polymorphisms. Therefore, mutations in two major genes required for gonadal development, SRY and WT1, are not responsible for XY partial gonadal dysgenesis.3817-2

The Novel P.e89k Mutation In The Sry Gene Inhibits Dna Binding And Causes The 46,xy Disorder Of Sex Development.

Male sex determination in humans is controlled by the SRY gene, which encodes a transcriptional regulator containing a conserved high mobility group box domain (HMG-box) required for DNA binding. Mutations in the SRY HMG-box affect protein function, causing sex reversal phenotypes. In the present study, we describe a 19-year-old female presenting 46,XY karyotype with hypogonadism and primary amenorrhea that led to the diagnosis of 46,XY complete gonadal dysgenesis. The novel p.E89K missense mutation in the SRY HMG-box was identified as a de novo mutation. Electrophoretic mobility shift assays showed that p.E89K almost completely abolished SRY DNA-binding activity, suggesting that it is the cause of SRY function impairment. In addition, we report the occurrence of the p.G95R mutation in a 46,XY female with complete gonadal dysgenesis. According to the three-dimensional structure of the human SRY HMG-box, the substitution of the conserved glutamic acid residue by the basic lysine at position 89 introduces an extra positive charge adjacent to and between the positively charged residues R86 and K92, important for stabilizing the HMG-box helix 2 with DNA. Thus, we propose that an electrostatic repulsion caused by the proximity of these positive charges could destabilize the tip of helix 2, abrogating DNA interaction.44361-

Screening for mutations in the GJB3 gene in Brazilian patients with nonsyndromic deafness

Abstract. Deafness is a complex disorder that is affected by a high number of genes and environmental factors. Recently, enormous progress has been made in nonsyndromic deafness research, with the identification of 90 loci and 33 nuclear and 2 mitochondrial genes involved (http://dnalab-www.uia.ac.be/dnalab/hhh/). Mutations in the GJB3 gene, encoding the gap junction protein connexin 31 (Cx31), have been pathogenically linked to erythrokeratodermia variabilis and nonsyndromic autosomal recessive or dominant hereditary hearing impairment. To determine the contribution of the GJB3 gene to sporadic deafness, we analysed the GJB3 gene in 67 families with nonsyndromic hearing impairment. A single coding exon of the GJB3 gene was amplified from genomic DNA and then sequenced. Here we report on three amino acid changes: Y177D (c.529T > G), 49delK (c.1227C > T), and R32W (c.144-146delGAA). The latter substitution has been previously described, but its involvement in hearing impairment remains uncertain. We hypothesize that mutations in the GJB3 gene are an infrequent cause of nonsyndromic deafness

Evaluation of insulin resistance and lipid profile in turner syndrome

OBJECTIVE: To evaluate the presence of insulin resistance (IR) and changes in lipid profile in Turner Syndrome (TS), and to check the influence of age, karyotype, systemic arterial hypertension (SAH), height, weight, body mass index (BMI), and pubertal development. PATIENTS AND METHODS: A transversal study of 35 TS patients, confirmed with karyotype (5 to 43 years), without previous use of anabolic steroid or hGH, with evaluation of blood pressure, pubertal development, anthropometric data, measurement of waist (W), hip (H), W to H ratio, total cholesterol, HDL, triglycerides (TGC), LDL, insulin and glucose. HOMA and QUICKI indexes were calculated, as well as glucose to insulin ratio (G/I). Data were examined by the Mann-Whitney and Spearman tests. RESULTS: Ten patients were >20 years. Seventeen had a 45,X karyotype and 6 structural aberrations; differences of the variables in relation to the karyotypes were not observed; 15 were nonpubertal and 20 pubertal; TGC and HOMA were significantly higher in puberty, while G/I was lower. Seven had normal height, 8 had BMI >25Kg/m2 (6 between 25 and 30, and 2 >30), and 19 W/H >0.85. Cholesterol levels were 180 ± 42mg% (4 >240); HDL 57 ± 16mg%; LDL 99 ± 34mg%; TGC 108 ± 96mg% (2 >200); HOMA 1.01 ± 0.71; QUICKI 0.4 ± 0.04 and G/I 23.5 ± 12.1 (2 20 anos. O cariótipo 45,X ocorreu em 17, e 6 com aberrações estruturais; não houve diferenças das variáveis em relação aos cariótipos. Quinze eram impúberes e 20 púberes; os TGC e o HOMA foram significativamente maiores na puberdade, e a G/I menor. Sete com estatura normal, 8 com IMC >25Kg/m2 (6 entre 25 e 30, e 2 >30), 19 com C/Q >0,85. O colesterol foi de 180 ± 42mg% (4 >240); o HDL de 57 ± 16mg%; o LDL de 99 ± 34mg%; os TGC de 108 ± 96mg% (2 >200); o HOMA de 1,01 ± 0,71; o QUICKI de 0,4 ± 0,04 e a G/I de 23,5 ± 12,1 (2 <7,0). CONCLUSÕES: Observaram-se alterações no perfil lipídico independentemente de faixa etária, cariótipo, PA e obesidade, porém agravadas pela RI, que foi menos freqüente do que descrita na literatura, parecendo relacionada à idade cronológica, obesidade e reposição estrogênica.278285Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Homozygous Inactivating Mutation In Nanos3 In Two Sisters With Primary Ovarian Insufficiency.

Despite the increasing understanding of female reproduction, the molecular diagnosis of primary ovarian insufficiency (POI) is seldom obtained. The RNA-binding protein NANOS3 poses as an interesting candidate gene for POI since members of the Nanos family have an evolutionarily conserved function in germ cell development and maintenance by repressing apoptosis. We performed mutational analysis of NANOS3 in a cohort of 85 Brazilian women with familial or isolated POI, presenting with primary or secondary amenorrhea, and in ethnically-matched control women. A homozygous p.Glu120Lys mutation in NANOS3 was identified in two sisters with primary amenorrhea. The substituted amino acid is located within the second C2HC motif in the conserved zinc finger domain of NANOS3 and in silico molecular modelling suggests destabilization of protein-RNA interaction. In vitro analyses of apoptosis through flow cytometry and confocal microscopy show that NANOS3 capacity to prevent apoptosis was impaired by this mutation. The identification of an inactivating missense mutation in NANOS3 suggests a mechanism for POI involving increased primordial germ cells (PGCs) apoptosis during embryonic cell migration and highlights the importance of NANOS proteins in human ovarian biology.201478746

Modelling adult Aedes aegypti and Aedes albopictus survival at different temperatures in laboratory and field settings.

BACKGROUND: The survival of adult female Aedes mosquitoes is a critical component of their ability to transmit pathogens such as dengue viruses. One of the principal determinants of Aedes survival is temperature, which has been associated with seasonal changes in Aedes populations and limits their geographical distribution. The effects of temperature and other sources of mortality have been studied in the field, often via mark-release-recapture experiments, and under controlled conditions in the laboratory. Survival results differ and reconciling predictions between the two settings has been hindered by variable measurements from different experimental protocols, lack of precision in measuring survival of free-ranging mosquitoes, and uncertainty about the role of age-dependent mortality in the field. METHODS: Here we apply generalised additive models to data from 351 published adult Ae. aegypti and Ae. albopictus survival experiments in the laboratory to create survival models for each species across their range of viable temperatures. These models are then adjusted to estimate survival at different temperatures in the field using data from 59 Ae. aegypti and Ae. albopictus field survivorship experiments. The uncertainty at each stage of the modelling process is propagated through to provide confidence intervals around our predictions. RESULTS: Our results indicate that adult Ae. albopictus has higher survival than Ae. aegypti in the laboratory and field, however, Ae. aegypti can tolerate a wider range of temperatures. A full breakdown of survival by age and temperature is given for both species. The differences between laboratory and field models also give insight into the relative contributions to mortality from temperature, other environmental factors, and senescence and over what ranges these factors can be important. CONCLUSIONS: Our results support the importance of producing site-specific mosquito survival estimates. By including fluctuating temperature regimes, our models provide insight into seasonal patterns of Ae. aegypti and Ae. albopictus population dynamics that may be relevant to seasonal changes in dengue virus transmission. Our models can be integrated with Aedes and dengue modelling efforts to guide and evaluate vector control, better map the distribution of disease and produce early warning systems for dengue epidemics

Evidences for subclinic chronic autoimmune thyroid disease in girls with Turner Syndrome

Patients with Turner syndrome (TS) frequently exhibit transient, recurrent and asymptomatic variations of TSH and/or thyroid hormones (TH). This work was carried out to evaluate thyroid function and structure in patients with TS who had had such variations in hormone concentrations. Our sample comprised 24 patients, 17 less than 20-years old. Evaluation included serum levels of TSH, free T4, total T3, TPO and Tg autoantibodies, thyroid ultrasound (US) and scintigraphy with 99mTc-pertechnetate. Thirteen patients had abnormal TSH and/or TH levels; 23 exhibited US features compatible with chronic thyroid disorder, particularly thyromegaly (established according to volume expected for stature) and heterogeneous echogenicity. Uptake was normal in 21 cases and tracer distribution was homogeneous in 22. The finding of abnormal hormone concentrations was independent of age, length of time since the first similar finding, thyroid autoantibodies, number of abnormalities at US and abnormal scintigraphic findings. Patients aged more than 20 years had higher frequency of thyroid antibodies and heterogeneous echogenicity, and thyroid volume was significantly correlated to length of time since detection of the first hormone variation, indicating progressive thyroid disease. These results suggest that subclinical thyroid dysfunction in TS is due to chronic autoimmune thyroid disease.O seguimento de pacientes com síndrome de Turner (ST) freqüentemente revela alterações transitórias, recorrentes e assintomáticas de TSH e/ou hormônios tireóideos (HT). Neste trabalho foram avaliadas estrutura e função da tireóide em portadoras da ST com história de alterações prévias desses hormônios. A casuística incluiu 24 pacientes, 17 com menos de 20 anos, avaliadas laboratorialmente pelas concentrações séricas de TSH, T4 livre, T3 e anticorpos anti-TPO e anti-Tg, e morfologicamente por ultra-sonografia (USG) e cintilografia com pertecnetato-99mTc. Havia alterações de TSH e/ou HT em 13 casos, e em 23 havia alterações USG compatíveis com doença crônica da tireóide, particularmente tireomegalia (estabelecida de acordo com o volume esperado para a estatura) e heterogeneidade do parênquima. A captação foi normal em 21 casos e a distribuição do radiofármaco, homogênea em 22. As alterações hormonais foram independentes da idade, do tempo de evolução, da presença de anticorpos, do número de anomalias USG e de alterações cintilográficas. Pacientes maiores de 20 anos apresentaram maior freqüência de anticorpos e de hipoecogenicidade do parênquima, e houve correlação positiva entre o volume tireóideo e o tempo de evolução, indicando comprometimento progressivo da glândula. Esses resultados sugerem que as alterações encontradas decorram de doença tireóidea auto-imune crônica.401409Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES