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1.
Genet Mol Res ; 13(4): 9068-76, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25366798

RESUMEN

Turner syndrome (TS) is characterized by the presence of one full X chromosome and total or partial deletion of the second sex chromosome. Diagnosis of TS is often delayed, resulting in inappropriate treatment. Early diagnosis of TS using a neonatal screening test may improve preventive measures and treatment, thus improving patient quality of life. The goal of this study was to standardize a neonatal TS screening algorithm. Two study genes (ARSE and MAGEH1) and 1 normalizing gene (HBB) were used to detect the second X chromosome. We screened 996 newborns whose peripheral blood was collected and stored in filter paper. In addition, samples from 20 patients with confirmed diagnosis of TS were included in the study. Relative amounts of ARSE/HBB were determined using real-time polymerase chain reaction. The cutoff at the 5th percentile was arbitrarily set to indicate repetition of the test. The test was repeated in 51/1016 patients with ARSE/HBB < 0.81. For 10 samples with values persistently <0.81, we quantified the MAGEH1/HBB ratio. Values below the 95th percentile in TS patients (MAGEH1/HBB < 1.24) were considered to be inadequate. Only 6/996 NB showed inadequate values for the 2 studied genes, which were recalled for clinical evaluation and karyotype testing. Analysis of 20 patients diagnosed with TS allowed for identification of false-negatives and true-positives, establishing 95% sensitivity when the indicated cutoff values were used. In conclusion, our algorithm reached 95% detection sensitivity with an acceptable recall rate (0.6%), allowing for the detection of suspected TS cases in the neonatal period.


Asunto(s)
Arilsulfatasas/genética , Pruebas Genéticas/métodos , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Neoplasias/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Síndrome de Turner/genética , Algoritmos , Femenino , Humanos , Recién Nacido , Cariotipo , Cariotipificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Síndrome de Turner/diagnóstico , Globinas beta/genética
2.
Genet Mol Res ; 12(2): 1834-40, 2013 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-23479164

RESUMEN

Normal testosterone levels are frequently observed in women with androgenetic alopecia (AGA), suggesting the involvement of androgen sensitivity in this condition. Androgen sensitivity is related to androgen receptor (AR) messenger RNA (mRNA) production in hair follicles and is negatively related to the number of CAG repeats present in exon 1 of the AR gene. The aim of this study was to compare AR expression in AGA women with normal controls and to correlate this expression with the number of CAG repeats. Hair follicles were obtained from 27 women with AGA and 21 controls for AR gene expression analysis. AR expression was evaluated through AR mRNA quantification using real-time polymerase chain reaction and the number of CAG repeats in the AR gene was determined in complementary DNA samples obtained from hair follicles and analyzed with the Gene Scan software. AR mRNA in the frontal-parietal region was significantly higher than in the occipital region of AGA patients (paired t-test, P = 0.046). No significant difference was identified in controls (P = 0.67). Both regions in the same individual showed a significant positive correlation in AGA patients (r = 0.77; P < 0.05) and in controls (r = 0.91; P < 0.05). A negative correlation was identified between AR expression and the number of CAG repeats only in AGA patients (r = 0.510; P = 0.013). The identification of elevated AR mRNA quantitation in hair follicles is a useful tool for identifying potentially abnormal androgen sensitivity in AGA patients.


Asunto(s)
Alopecia/genética , Folículo Piloso/metabolismo , Receptores Androgénicos/genética , Adulto , Anciano , Alelos , ADN Complementario/genética , Exones/genética , Femenino , Regulación de la Expresión Génica , Técnicas de Genotipaje , Humanos , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Androgénicos/metabolismo , Expansión de Repetición de Trinucleótido/genética , Adulto Joven
3.
Genet Mol Res ; 11(4): 3975-87, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23212335

RESUMEN

Insulin resistance is an underlying cause of metabolic changes associated with cardiovascular diseases. Glucocorticoids are known determinant factors of insulin resistance. We quantified glucocorticoid receptor alpha (GRα) mRNA and 11 beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) mRNA in various tissues of 35 patients with previously established cardiovascular disease. This was a prospective study in a cardiac surgery patient setting. Samples of subcutaneous adipose tissue, epicardial fat, muscle, and peripheral blood mononuclear cells were examined. GRα and 11ß-HSD1 mRNA were determined by real-time PCR. Mean age was 54.4 years. A significantly higher level of GRα mRNA was observed in muscle, with mean = 43.6 arbitrary units, median (p25-p75) = 39.4, compared to epicardial adipose tissue, with mean = 34.2, median (p25-p75) = 27.6, and to subcutaneous adipose tissue, with mean = 29.0, median (p25-p75) = 19.0, and lymphocytes, with mean = 17.5, median (p25-p75) = 14.02. When patients with diabetes mellitus were compared to patients without insulin resistance, significantly lower levels of GRα mRNA were observed in epicardial fat. Lymphocytes had the lowest 11ß-HSD1 mRNA concentration. We also observed significantly reduced 11ß-HSD1 mRNA levels in visceral fat when compared with muscle tissue. GRα and 11ß-HSD1 mRNA levels differed among tissues involved in the pathophysiology of metabolic syndrome. We conclude that epicardial adipose tissue has lower GRαmRNA levels in insulin-resistant patients; this seems to be an adaptive and protective mechanism.


Asunto(s)
Adaptación Fisiológica/genética , Resistencia a la Insulina/genética , Especificidad de Órganos/genética , Receptores de Glucocorticoides/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Adulto , Anciano , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/cirugía , Femenino , Regulación de la Expresión Génica , Humanos , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Grasa Intraabdominal/fisiopatología , Masculino , Persona de Mediana Edad , Pericardio/metabolismo , Pericardio/patología , Pericardio/fisiopatología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Glucocorticoides/metabolismo
4.
Horm Metab Res ; 42(9): 677-81, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20422505

RESUMEN

Turner syndrome (TS) is the complete or partial loss of the second sex chromosome, occurring in 1:5 000 girls. Early recognition allows appropriate therapy for short stature and puberty. Neonatal diagnosis of TS permits detection of associated malformations, minimizing sequels. Aiming to develop a molecular method for the diagnosis of TS we employed blood samples stored on filter paper. We evaluated 78 female controls, 25 TS girls with 45,X karyotype, and 32 TS patients with other karyotypes. After DNA extraction, samples were submitted to real-time PCR, using primers and probes directed to the study gene ARSE and to the control gene GAPDH. A ROC curve established the ARSE:GAPDH ratio with a cutoff value of 0.7. Low ARSE:GAPDH ratio of <0.7 was present in 100% of 45,X TS patients. This cutoff value presented a sensitivity of 100% and a specificity of 100% in detecting 45,X TS patients with a positive predictive value of 100% and a negative predictive value of 100%. The same cutoff value was able to identify only 56% of TS with other karyotypes, in which we observed a mean (SD) ARSE:GAPDH ratio=0.66 (0.2); and the interquartile range=0.4-0.8. Determination of ARSE:GAPDH ratio is a fast, sensitive, and specific method, with viable cost and feasible automation, which makes it potentially applicable in neonatal screening programs for the diagnosis of Turner syndrome 45,X.


Asunto(s)
Tamizaje Neonatal/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Síndrome de Turner/diagnóstico , Síndrome de Turner/genética , Arilsulfatasas/genética , Estudios de Casos y Controles , Dosificación de Gen/genética , Humanos , Recién Nacido , Cariotipificación
5.
Genet Mol Res ; 9(2): 1045-53, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20568049

RESUMEN

The glutathione S-transferase (GST) family consists of phase II detoxification enzymes that catalyze the conjugation of toxic substances, such as chemotherapeutic agents, to glutathione. We examined whether GSTT1/GSTT1"null", GSTM1/GSTM1"null" and GSTP1Ile105Ile/GSTP1Ile105Val polymorphisms are associated with different response rates to neoadjuvant chemotherapy in the treatment of stage II and III breast cancer. Forty Brazilian women with invasive ductal adenocarcinoma of the breast submitted to neoadjuvant chemotherapy, using 5-fluorouracil, epirubicin and cyclophosphamide, were genotyped for the GSTT1, GSTM1 and GSTP1 genes. Clinical response was assessed by RECIST criteria. Comparisons were made for the three genes alone and in pairs, as polymorphic and as wild-type combinations and polymorphic/wild-type combinations. We analyzed all possible combinations and their response rate. Patients with the GSTT1/GSTP1105Ile combination were found to have a significantly better response than GSTT1"null"/GSTP1105Val (P = 0.0209) and GSTT1/GSTM1 (P = 0.0376) combinations. Analysis of all possible combinations showed the GSTM1"null" polymorphic genotype to be present in four, and the wild-type GSTP1105Ile in six of the combinations associated with the largest number of responding patients. We found that patients with the GSTT1/GSTP1105Ile wild-type combination had a significantly higher response rate to chemotherapy than patients with the respective polymorphic GSTT1"null"/GSTP1105Val combination or patients with the wild-type GSTT1/GSTM1. The six gene combinations associated with the largest number of responding patients were found to contain the wild-type GSTP1105Ile and the polymorphic-type GSTM1"null". These specific combinations were virtually absent in the combinations with few responding patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Gutatión-S-Transferasa pi/genética , Glutatión Transferasa/genética , Polimorfismo Genético , Adulto , Anciano , Brasil , Neoplasias de la Mama/enzimología , Carcinoma Ductal de Mama/genética , Ciclofosfamida/uso terapéutico , Epirrubicina/uso terapéutico , Femenino , Fluorouracilo/uso terapéutico , Glutatión/metabolismo , Humanos , Persona de Mediana Edad , Resultado del Tratamiento
6.
Horm Res ; 71(2): 94-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19129714

RESUMEN

BACKGROUND/AIMS: While laboratory methods for the detection of testicular tissue are well standardized, currently there is no available test to demonstrate the presence of ovarian tissue. We evaluated the effectiveness of gonadal stimulation with luteinizing hormone (LH)/follicle-stimulating hormone (FSH) for the detection of ovarian tissue in patients with disorders of sex development (DSD). METHODS: Ten patients with congenital adrenal hyperplasia (CAH) as ovarian-positive controls, 10 with cryptorchidism (ovarian-negative controls), 13 patients with DSD of no defined etiology and 7 patients with ovotesticular DSD (true hermaphroditism, TH) were included in the study. They underwent a daily injection of both LH and FSH on 3 consecutive days. LH, FSH, estradiol, testosterone and inhibin A were measured before treatment, 24 h after the 1st dose and 24 h after the 3rd dose. RESULTS: Estradiol increased in all CAH and TH patients, with a median value of 155.1 and 92.6 pg/ml, respectively, after the 3rd injection. Inhibin A also increased in all CAH and TH patients, with a median value of 70.4 and 32.2 pg/ml, respectively, after the 3rd injection. There was no change in these hormones in the other groups. CONCLUSION: The LH/FSH stimulation test might be a useful method to detect the presence of ovarian tissue.


Asunto(s)
Trastornos del Desarrollo Sexual/sangre , Hormona Folículo Estimulante/administración & dosificación , Hormonas/administración & dosificación , Inhibinas/sangre , Hormona Luteinizante/administración & dosificación , Ovario , Adolescente , Niño , Preescolar , Estradiol/sangre , Femenino , Humanos , Lactante , Masculino
7.
Genet Mol Res ; 7(1): 43-9, 2008 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-18273818

RESUMEN

Turner syndrome (TS) is one of the most common chromosomal abnormalities among girls. Complete monosomy of X chromosome is responsible for almost 50% of all cases of TS, and mosaicism and X anomaly are detected in the other half. It has already been demonstrated that early diagnosis of these children allows appropriate growth hormone treatment with better final height prognosis and introduction of estrogen at an ideal chronological age. Sixty-four short-stature girls were selected and the clinical data obtained were birth weight and height, weight and height at the first medical visit and target height. Other clinical data including cardiac and renal abnormalities, otitis, Hashimoto thyroiditis, cubitus valgus, short neck, widely separated nipples, and pigmented nevi were obtained from the patients' medical records. The aim of the present study was to evaluate the screening of a group of short-stature girls for TS based on the number of CAG repeats of the androgen receptor gene analyzed by GeneScan software. Patient samples with two alleles (heterozygous) were 49/64 (76.5%) and with one allele (homozygous) were 15/64 (23.5%). A karyotype was determined in 30 patients, 9 homozygous and 21 heterozygous. In the homozygous group, 6/9 were 45,X and 3/9 were 46,XX. In the heterozygous group, 17/21 were 46,XX, and 4/21 were TS patients with mosaicism (45,X/46,XX; 45,X/46XiXq; 46XdelXp). The pattern obtained by GeneScan in two patients with mosaicism in the karyotype was an imbalance between the peak heights of the two alleles, suggesting that this imbalance could be present when there is a mosaicism. The frequency of TS abnormalities (18.7%) did not differ between TS and 46,XX girls. Thus, it is important to accurately assess the incidence of TS in growth-retarded girls, even in the absence of other dysmorphisms. In this study, we diagnosed 6 cases of TS 45,X (9.4%) by molecular analysis, with a 100% sensitivity and 85% specificity. This molecular analysis was able to detect all cases of TS 45,X and the majority of mosaicisms, without the need for more X chromosome markers. In conclusion, determining the number of CAG repeats of the androgen receptor gene analyzed by GeneScan was a fast method with high sensitivity for the detection of TS 45,X, suggesting that it could be interesting as a method for screening a population of growth-retarded girls.


Asunto(s)
Estatura/genética , Exones , Receptores Androgénicos/genética , Repeticiones de Trinucleótidos/genética , Síndrome de Turner/diagnóstico , Alelos , Niño , Femenino , Marcadores Genéticos , Heterocigoto , Homocigoto , Humanos , Cariotipificación , Mosaicismo , Sensibilidad y Especificidad , Estadística como Asunto , Factores de Tiempo
8.
Genet Mol Res ; 6(2): 277-83, 2007 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-17573657

RESUMEN

Adrenal hypoplasia congenita (AHC) is a rare disease that can be caused by many abnormalities, including an X-linked form. Mutations in the DAX1 gene have been assigned as the genetic cause of AHC. We describe here three siblings with AHC, clinically presented at different ages, two in the neonatal period and one oligosymptomatic during infancy. Molecular analysis was able to detect a novel mutation in exon 1 of the DAX1 gene, consisting of a transition of C to T at position 359, determining a stop codon at position 359 (Q359X). The mutated gene encodes a truncated protein missing a large portion of the ligand-binding domain (C-terminal domain). The recognition of the disease in the index case suggested the diagnosis in the other siblings. Interestingly, the same mutation is presented with different phenotypes, suggesting that first-degree family members of patients with DAX1 mutations should be carefully evaluated routinely.


Asunto(s)
Insuficiencia Suprarrenal/genética , Codón sin Sentido , Proteínas de Unión al ADN/genética , Mutación Puntual , Receptores de Ácido Retinoico/genética , Proteínas Represoras/genética , Niño , Preescolar , Receptor Nuclear Huérfano DAX-1 , Exones , Familia , Femenino , Humanos , Lactante , Masculino , Linaje , Fenotipo , Hermanos
9.
J Med Genet ; 41(5): 354-9, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15121773

RESUMEN

The R337H TP53 mutation is a low-penetrance molecular defect that predisposes to adrenocortical tumour (ACT) formation in Brazilian and possibly other populations. Additional genetic defects may be responsible for the variable expression of ACTs in these cases. The inhibin alpha-subunit gene (INHA) on 2q33-qter has been implicated in mouse adrenocortical tumourigenesis. We studied 46 pediatric patients with ACTs from Brazil for INHA genetic alterations; 39 of these patients were heterozygous carriers of the R337H TP53 mutation. We first mapped the INHA gene by radiation hybrid analysis and determined 10 linked microsatellite markers in an area flanked by D2S1371 and D2S206 on 2q33-qter. These markers were then used for loss of heterozygozity (LOH) studies in nine paired germline and tumour DNA samples. Mapping placed the INHA gene in close proximity to D2S2848 (SHGC11864) with a log of odds (LOD) score of 5.84. LOH for at least one marker in the region was identified in 8/9 tumours (89%). Six patients were heterozygous for three INHA mutations: one in exon 1, 127C>G, and two in exon 2, 3998G>A and 4088G>A, all leading to amino acid substitutions (P43A, G227R, and A257T, respectively). A257T is located in a conserved INHA region, highly homologous to transforming growth factor-beta; both G227R and A257T change polarity, and, in addition, G227R changes the pH. We conclude that these sequence alterations and the detected 2q allelic changes suggest that INHA may be one of the contributing factors needed for ACT formation in pediatric patient carriers of the R337H TP53 mutation.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Genes p53 , Inhibinas/genética , Mutación , Sustitución de Aminoácidos , Niño , Mapeo Cromosómico , Análisis Mutacional de ADN , Heterocigoto , Humanos , Pérdida de Heterocigocidad
10.
Horm Metab Res ; 40(10): 718-21, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18553256

RESUMEN

The activity of the hypothalamic-pituitary-adrenal axis is usually modulated by several stress factors, including exercise. Different responses are induced by physical training according to duration and intensity of exercise. During prolonged training, cortisol remains normal or decreased as a consequence of altered cortisol secretion, metabolism and excretion, and possibly by changes in glucocorticoid sensitivity. The aim of this study was to evaluate the impact of prolonged physical training on the glucocorticoid sensitivity. Eighteen cadets of the Air Force Academy, mean (SD) age: 18.7 (1.0) years, underwent an intensive 6-week preparatory training-period considered adequate by inducing significant changes on body composition measured by bioelectrical impedance. Measurement of individual's pituitary glucocorticoid sensitivity was done by an intravenous very low dose dexamethasone suppression test (20 microg/m (2)) that was performed before and after the training period. Cortisol levels were obtained at basal condition and 120 minutes after the dexamethasone infusion. Basal cortisol showed a significant decrease after prolonged training. The percent cortisol suppression after dexamethasone tended to be lower after the training period. Overall, our data suggest that prolonged physical training is able to reduce glucocorticoid sensitivity, which can have a beneficial impact in chronic stress conditions.


Asunto(s)
Dexametasona/administración & dosificación , Dexametasona/farmacología , Ejercicio Físico/fisiología , Glucocorticoides/administración & dosificación , Glucocorticoides/farmacología , Hipófisis/efectos de los fármacos , Adolescente , Adulto , Antropometría , Composición Corporal/efectos de los fármacos , Brasil , Relación Dosis-Respuesta a Droga , Impedancia Eléctrica , Humanos , Hidrocortisona/sangre , Inyecciones Intravenosas , Masculino , Personal Militar
11.
Brain Cogn ; 50(2): 316-23, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12464198

RESUMEN

We have studied the relationship between dehydroepiandrosterone sulfate (DHEAS), cortisol, and cognitive function in a population of demented patients (n=29), age-matched controls (n=46), and younger subjects (n=11). All were submitted to morning collection of blood for determination of plasma cortisol and DHEAS measured by 125I radioimmunoassay. DHEAS levels and cortisol/DHEAS ratios were significantly different among groups with higher DHEAS levels and lower cortisol/DHEAS ratios in younger people (Bonferroni p<.05). Cortisol levels were associated to the presence of dementia (Odds ratio=.93; 95% CI,.86-1.01). There was no difference between DHEAS levels of demented and age-matched controls; however, demented patients showed a trend for higher cortisol/DHEAS ratios than age-matched controls and the latter showed higher ratio values than younger subjects. DHEAS and cortisol plasma values were significantly correlated in all individuals (p<.01). In this study cortisol was independently associated to the presence of dementia.


Asunto(s)
Envejecimiento/fisiología , Enfermedad de Alzheimer/metabolismo , Trastornos del Conocimiento/metabolismo , Sulfato de Deshidroepiandrosterona/sangre , Hidrocortisona/sangre , Anciano , Anciano de 80 o más Años , Encéfalo/metabolismo , Trastorno Depresivo Mayor/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Genet. mol. res. (Online) ; 7(1): 43-49, Jan. 2008. tab, ilus
Artículo en Inglés | LILACS | ID: lil-553769

RESUMEN

Turner syndrome (TS) is one of the most common chromosomal abnormalities among girls. Complete monosomy of X chromosome is responsible for almost 50% of all cases of TS, and mosaicism and X anomaly are detected in the other half. It has already been demonstrated that early diagnosis of these children allows appropriate growth hormone treatment with better final height prognosis and introduction of estrogen at an ideal chronological age. Sixty-four short-stature girls were selected and the clinical data obtained were birth weight and height, weight and height at the first medical visit and target height. Other clinical data including cardiac and renal abnormalities, otitis, Hashimoto thyroiditis, cubitus valgus, short neck, widely separated nipples, and pigmented nevi were obtained from the patients’ medical records. The aim of the present study was to evaluate the screening of a group of short-stature girls for TS based on the number of CAG repeats of the androgen receptor gene analyzed by GeneScan software. Patient samples with two alleles (heterozygous) were 49/64 (76.5%) and with one allele (homozygous) were 15/64 (23.5%). A karyotype was determined in 30 patients, 9 homozygous and 21 heterozygous. In the homozygous group, 6/9 were 45,X and 3/9 were 46,XX. In the heterozygous group, 17/21 were 46,XX, and 4/21 were TS patients with mosaicism (45,X/46,XX; 45,X/46XiXq; 46XdelXp). The pattern obtained by GeneScan in two patients with mosaicism in the karyotype was an imbalance between the peak heights of the two alleles, suggesting that this imbalance could be present when there is a mosaicism. The frequency of TS abnormalities (18.7%) did not differ between TS and 46,XX girls. Thus, it is important to accurately assess the incidence of TS in growth-retarded girls, even in the absence of other dysmorphisms. In this study, we diagnosed 6 cases of TS 45,X (9.4%) by molecular analysis, with a 100% sensitivity and 85% specificity. This molecular analysis was...


Asunto(s)
Humanos , Femenino , Niño , Exones , Estatura/genética , Receptores Androgénicos/genética , Repeticiones de Trinucleótidos/genética , Síndrome de Turner/diagnóstico , Alelos , Marcadores Genéticos , Heterocigoto , Homocigoto , Mosaicismo , Sensibilidad y Especificidad , Estadística como Asunto , Factores de Tiempo
13.
Genet. mol. res. (Online) ; 6(2): 277-283, 2007. ilus, tab
Artículo en Inglés | LILACS | ID: lil-482043

RESUMEN

Adrenal hypoplasia congenita (AHC) is a rare disease that can be caused by many abnormalities, including an X-linked form. Mutations in the DAX1 gene have been assigned as the genetic cause of AHC. We describe here three siblings with AHC, clinically presented at different ages, two in the neonatal period and one oligosymptomatic during infancy. Molecular analysis was able to detect a novel mutation in exon 1 of the DAX1 gene, consisting of a transition of C to T at position 359, determining a stop codon at position 359 (Q359X). The mutated gene encodes a truncated protein missing a large portion of the ligand-binding domain (C-terminal domain). The recognition of the disease in the index case suggested the diagnosis in the other siblings. Interestingly, the same mutation is presented with different phenotypes, suggesting that first-degree family members of patients with DAX1 mutations should be carefully evaluated routinely.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Codón sin Sentido , Insuficiencia Suprarrenal/genética , Mutación Puntual , Proteínas Represoras/genética , Proteínas de Unión al ADN/genética , Receptores de Ácido Retinoico/genética , Familia , Fenotipo , Hermanos , Linaje , Exones
14.
Genet. mol. res. (Online) ; 4(4): 749-754, 2005. ilus
Artículo en Inglés | LILACS | ID: lil-444848

RESUMEN

Turner syndrome (TS) is one of the most common human chromosomal abnormalities; it is characterized by the presence of one normal X chromosome and the complete or partial loss of the second X chromosome. The early recognition of TS patients allows for adequate therapy for short stature and pubertal sex steroid substitution. We developed a cost-effective molecular diagnostic tool that can be used to identify 45,X TS patients from dried blood spots, for possible use in neonatal screening for TS. We used a three-step method for 45,X TS detection: i) DNA extraction from dried blood spot samples, ii) pre-PCR HpaII digestion (methylation-sensitive enzyme) and iii) GeneScan analysis of selected cases. DAX-1 gene amplification was used to recognize DNA integrity, and the androgen receptor gene (Xq11-12), which is both a highly polymorphic and methylated gene, was used to determine the number of X chromosome alleles. Using this three-step diagnostic procedure, we detected apparent TS in 1/304 (0.33%) samples; such individuals should be submitted to clinical examination and karyotype confirmation. The three-step 45,X TS neonatal screening protocol is a simple, reliable, fast (under 30 h) and cost-effective diagnostic tool, useful for the neonatal detection of TS.


Asunto(s)
Humanos , Femenino , Recién Nacido , ADN , Pruebas Genéticas , Síndrome de Turner/diagnóstico , Tamizaje Neonatal/métodos , ADN , Pruebas Genéticas , Análisis Costo-Beneficio , Recolección de Muestras de Sangre , Metilación de ADN , Reacción en Cadena de la Polimerasa , Receptores Androgénicos/genética , Síndrome de Turner/genética , Tamizaje Neonatal/economía
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