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1.
Cutan Ocul Toxicol ; 36(4): 387-392, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28351163

RESUMO

BACKGROUND: Chronic spontaneous urticaria (CSU) is a common dermatological condition defined by the sudden occurrence of daily wheals and pruritus for at least six weeks. Multifactorial origin is suggested such as oxidative stress. This latter may play a double role as a trigger and remnant agent. OBJECTIVES: The first aim of this study is to investigate antioxidant status, inflammatory proteins, hematologic counts and clinical assessment in CSU patients. The second aim is to evaluate the effect of a first-line treatment: desloratadine 5 mg/d on these different parameters. PATIENTS AND METHODS: This study enrolled 30 CSU patients and same number of controls. We assessed the urticaria activity score (UAS), total antioxidant status (TAS), glutathione S-transferase (GST), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), albumin, alpha1, alpha2, beta1 beta2, gamma globulins, c-reactive protein (CRP) and hematologic numeration. RESULTS: At baseline alpha1, alpha2, beta1, beta2, gamma globulins, CRP, SOD activity, leukocytes and basophils were significantly higher in patients versus controls (p < 0.05). TAS, GST, CAT, GPx and albumin were significantly low in patients versus controls (p < 0.05). After treatment, TAS, GST and GPx were significantly increased in patients versus patients before treatment (p < 0.001). SOD, alpha1, alpha2, beta1, beta2, gamma globulins, CRP, albumin, leukocytes and basophils were significantly decreased after treatment versus before treatment (p < 0.05). A significant correlation between CRP and UAS (r = 0.3; p = 0.011) was noted. UAS assessment revealed the efficacy of 30 d-antihistaminic treatment. CONCLUSIONS: Desloratadine exerted anti-inflammatory and antioxidant effects on CSU patients revealed by CRP. Patients' remission was synergistic to CRP attenuation emphasizing CRP relevance for CSU clinical assessment.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Proteína C-Reativa/análise , Loratadina/análogos & derivados , Urticária/tratamento farmacológico , Adulto , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Catalase/sangue , Doença Crônica , Feminino , Glutationa Peroxidase/sangue , Glutationa Transferase/sangue , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Antagonistas não Sedativos dos Receptores H1 da Histamina/uso terapêutico , Humanos , Loratadina/farmacologia , Loratadina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Superóxido Dismutase/sangue , Tunísia , Urticária/sangue , Urticária/patologia , Adulto Jovem
2.
Genet Mol Res ; 15(2)2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27173183

RESUMO

The association between the single nucleotide polymorphism rs762551 in the cytochrome P450 family 1, subfamily A2 gene (CYP1A2) and caffeine consumption remains controversial. We conducted a meta-analysis to clarify this potential association. Twelve studies were selected from articles retrieved from the and Google Scholar databases, and the data were analyzed to determine the odds ratio (OR) of genotypes AA (conferring fast caffeine metabolism) vs AC + CC (conferring slow caffeine metabolism). Comparisons were made between 6161 high caffeine consumers and 3219 low caffeine consumers. The overall analysis showed a significant association between genotype AA and coffee intake  [OR = 1.13, 95% confidence interval (CI) = 1.03-1.24; Q = 19.23, P = 0.06; I2 = 43%]. In subgroup analyses, the association was also found within male, younger, and Caucasian subjects (OR = 1.21, 95%CI = 1.08- 1.35; OR = 1.71, 95%CI = 1.18-2.48; OR = 1.29, 95%CI = 1.12-1.49, respectively) but not in female, older, and Asian subjects (OR = 0.98, 95%CI = 0.83-1.15; OR = 0.83, 95%CI = 0.56-1.22; OR = 0.91, 95%CI = 0.71-1.17, respectively). Therefore, the rs762551 AA genotype may lead to higher coffee intake, especially in males, younger age groups, and individuals of Caucasian ethnicity. Our data highlight the need to test other CYP1A2 polymorphisms showing significance in genome-wide association studies to clarify the association with caffeine intake in the Asian population.


Assuntos
Café , Citocromo P-450 CYP1A2/genética , Ingestão de Líquidos/genética , Comportamento Alimentar/etnologia , Polimorfismo de Nucleotídeo Único , Adulto , Fatores Etários , Idoso , Povo Asiático , Estudos de Casos e Controles , Ingestão de Líquidos/etnologia , Comportamento de Ingestão de Líquido , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , População Branca
3.
Rev Mal Respir ; 33(1): 32-40, 2016 Jan.
Artigo em Francês | MEDLINE | ID: mdl-26071129

RESUMO

INTRODUCTION: Several studies have investigated the clinical feature of COPD in subjects carrying the common alpha-1 antitrypsin deficiency mutations PIS and PIZ. However, there are few data on COPD due to rarer deficient variants. In this study, we aimed to explore the features of COPD in subjects carrying the PIMMmalton mutation, which is the most prevalent alpha-1 antitrypsin variant in Tunisia. MATERIAL AND METHODS: Five individuals, heterozygous for PIMMmalton were analyzed and compared to 97 non-deficient COPD patients. Demographic data as well as clinical and functional outcomes from subjects were collected. Blood gases and plasma alpha-1 antitrypsin levels were recorded. RESULTS: PIMMmalton subjects did not show any significant difference in terms of predicted FEV1 (35±13.2%), predicted forced vital capacity (34.2±9.6%) and FEV1 decline (148.6±114mL/year) compared to usual COPD patients (respectively 41.7±17.2%, P=0.500; 43.8±18.8%, P=0.300; 197.9±191mL/year, P=0.800). However, PaO2 was significantly reduced in PIMMmalton subjects (58.8±4.0mmHg) compared to usual COPD (69.9±10.6mmHg; P=0.029) and those patients with chronic bronchitis and centrolobular emphysema (71.0±10.9mmHg; P=0.038). CONCLUSION: PIMMmalton subjects were significantly hypoxic, similar to that observed in PiZZ homozygous rather than observed in heterozygous individuals.


Assuntos
Mutação , Doença Pulmonar Obstrutiva Crônica/genética , alfa 1-Antitripsina/genética , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Genet Mol Res ; 14(3): 8613-22, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26345792

RESUMO

Reactive oxygen species metabolizing enzymes may play an important role in the prevention of type-2 diabetes (T2D) complications. We analyzed the association between Cu/Zn-SOD +35 A/C, Mn-SOD T47C, and CAT -21 A/T gene polymorphisms and complications, in combination with tea consumption in Tunisian T2D. A sample of 366 T2D subjects was enrolled in this study. All participants were asked about tea consumption and frequency. Anthropometric, clinical, and routine biochemical characteristics were obtained from subjects' updated medical records. Malondialdehyde, as an early marker of lipid peroxidation, was measured in plasma samples. Urinary polyphenol derivatives (UPDs), as a marker of polyphenols intake, were assessed by the Folin-Ciocalteu assay. SODs and CAT genotypes were determined by conventional restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods. From all subjects, the results showed that in high tea consumers (>3 cups/day), the frequency of the Mn-SOD 47 CC genotype was significantly higher in T2D without complications compared with T2D with complications (P = 0.03; OR = 0.284; 95%CI = 0.086-0.939). However, no significant associations were observed with Cu/Zn-SOD +35 A/C or CAT -21 A/T genes polymorphisms. Additionally, the evaluation of UPDs showed that individuals carrying the Mn-SOD 47 CC genotype and consuming more than three cups of tea per day present significantly higher UPDs (P = 0.038). In conclusion, the Mn-SOD 47 C variant in combination with high tea consumption may provide protection against complications in T2D.


Assuntos
Complicações do Diabetes/genética , Diabetes Mellitus Tipo 2/genética , Superóxido Dismutase/genética , Chá , Catalase/genética , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Estresse Oxidativo , Fatores de Proteção , Tunísia
5.
Genet Mol Res ; 13(3): 5686-94, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25117326

RESUMO

Primer-introduced restriction analysis is widely used in molecular genetics. However, several studies have reported inconsistent data regarding sequencing, mainly among heterozygous samples. This discrepancy may be related to the bias towards a 1:1 ratio typically observed in heterozygous digestion products. In this study, we investigated the mechanism and minimization of this observed bias. Three mismatched polymerase chain reaction (PCR) models were analyzed by testing different PCR conditions and reaction mixtures. For EPHX1 gene rs1051740 single-nucleotide polymorphism PCR, DNA concentration, denaturation and elongation time, annealing temperature, and cycle number significantly influenced product ratios. For SERPINA1 gene PIMmalton deletion (ΔPhe52) and CHRNA3 gene rs1051730 single-nucleotide polymorphism PCRs, significant bias fluctuations were observed only for the annealing temperature and cycle number conditions. The relevance of these results to the amplification efficiency parameter is discussed. Rather than reducing the observed bias, our data provide evidence of a counterbalance for preferential amplification, depending on cycle number, annealing temperature, and amplification efficiency alteration. Our results are relevant for application to primer-introduced restriction analysis PCR assays.


Assuntos
Primers do DNA , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição
6.
Int J Immunogenet ; 39(2): 110-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22136554

RESUMO

Several polymorphisms in the complement components factor H and CFHR1 are associated with higher risk to develop atypical Haemolytic Uraemic Syndrome (aHUS) in Caucasians. We have determined the prevalence of these polymorphisms in Tunisian controls by using genetic and immunological techniques. No differences in the frequency of the factor H risk alleles c.-331C>T, c.2089A>G or c.2881G>T between Tunisian and Caucasians were found. On the contrary, the analysis of CFHR1 polymorphism revealed a higher frequency of Tunisian individuals homozygous for the CFHR1*Del (deleted) allele, and of individuals presenting the CFHR1*A phenotype. These results suggest distinct contributions of factor H and CFHR1 polymorphisms to aHUS in Tunisian and Caucasian populations.


Assuntos
Proteínas Inativadoras do Complemento C3b/genética , Fator H do Complemento/genética , Síndrome Hemolítico-Urêmica/genética , Polimorfismo Genético , População Branca/genética , Adulto , Alelos , Síndrome Hemolítico-Urêmica Atípica , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Etnicidade , Predisposição Genética para Doença/etnologia , Genoma Humano , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/etnologia , Síndrome Hemolítico-Urêmica/patologia , Homozigoto , Humanos , Fenótipo , Prevalência , Fatores de Risco , Tunísia/etnologia
7.
Genet Mol Res ; 9(2): 897-907, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20467983

RESUMO

Chronic obstructive pulmonary disease (COPD) is a multifactorial disease with possible genetic predisposition and involvement of various environmental factors. Several candidate genes have been reported as potentially associated with this lung disease. The glutathione S-transferase P1 gene (GSTP1) was proposed to be involved in susceptibility to develop COPD. It belongs to the GST family, which is a group of phase II enzymes that catalyze the glutathione conjugation of many endogenous and exogenous electrophilic compounds, such as carcinogens, therapeutic drugs, environmental toxins, and oxidative stress products. We conducted a case-control study to investigate genetic polymorphisms of this enzyme [exon 5 (Ile105Val) and exon 6 (Ala114Val)] in 234 unrelated COPD cases and 182 healthy controls from a Tunisian population. Genotyping was carried out using polymerase chain reaction and restriction fragment length polymorphism methods. GSTP1 Ala114/Val114 and Val114/Val114 genotypes were not found in either patients or healthy controls. However, there were differences in the distribution of various exon 5 GSTP1 genotypes between COPD patients and healthy controls. GSTP1 Val105/Val105 was significantly more common in patients compared to controls (OR = 2.67; 95%CI = 1.45-4.92; P = 0.0013). Multivariate logistic regression analysis confirmed a significant relationship between the mutant genotype and COPD (OR = 2.58; 95%CI = 1.31-5.09; P = 0.026), after adjustment for classic risk factors. Analysis of variance showed no correlation between age, body-mass index, pack-years, percentage of predicted FEV1 values, and any of the GSTP1 genotypes. We conclude that subjects with GSTP1 Val105 allele are at higher risk of COPD.


Assuntos
Glutationa S-Transferase pi/genética , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica/etnologia , Doença Pulmonar Obstrutiva Crônica/genética , Valina/genética , Idoso , Estudos de Casos e Controles , Éxons , Feminino , Glutationa/metabolismo , Glutationa S-Transferase pi/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Fatores de Risco , Tunísia
8.
Ann Biol Clin (Paris) ; 67(4): 441-5, 2009.
Artigo em Francês | MEDLINE | ID: mdl-19654085

RESUMO

Our study investigated alpha 1 antitrypsin deficiency (AATD) diagnosis in a family originated from central Tunisia and showing a familial history of asthma. Biochemical and genetic diagnosis for AATD was performed according to current diagnostic standards. AAT level quantification in affected individuals showed plasma AAT levels consistent with intermediate AATD (ranged from 0.91 to 1.04 g/L). The molecular analysis was assessed using the genotyping of the most prevalent PI*S and PI*Z SERPINA1 mutations and the sequencing of AAT coding exons for rare AATD variants detection. No PI*S or PI*Z deficient variants were seen in this family. Sequencing results showed the inheritance of the deficient rare variant PI*M(wurzburg) (P369S) at the heterozygous state in the mother and two affected siblings. However, AATD status remains unexplained in the third affected case, with no mutations detected in the AAT coding exons.


Assuntos
alfa 1-Antiquimotripsina/sangue , alfa 1-Antiquimotripsina/deficiência , Asma/genética , Éxons/genética , Feminino , Humanos , Masculino , Linhagem , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/genética , Testes de Função Respiratória , Tunísia , alfa 1-Antiquimotripsina/genética , alfa 1-Antitripsina/sangue , alfa 1-Antitripsina/genética
9.
Ann Biol Clin (Paris) ; 66(4): 379-84, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18725338

RESUMO

INTRODUCTION: more than 100 alleles have been described on the alpha 1 antitrypsin gene. Normal variants (PiM1, PiM2 and PiM3) encodes AAT molecules which are different but functional and normally secreted. The more frequent risk variants are PiS and PiZ. In this study, an AAT polymorphism analysis in correlation with pulmonary diseases was conducted. MATERIAL AND METHODS: analyses were performed on 96 asthmatics, 67 emphysema cases and 318 control subjects. Alpha 1 antitrypsin phenotypes were studied by quantitative determination of AAT concentration and isoelectrofocusing. Genotyping was performed by RFLP PCR. RESULTS: PiM1, PiM2, PiM3, PiS and PiZ allelic frequencies were calculated (0.7395, 0.2291, 0.0156, 0.0104, 0.0052 in asthmatics; 0.7547, 0.1716, 0.0298, 0.0298, 0.0149 in emphysema patients and 0.8030, 0.1525, 0.0408, 0.006, 0.0000 in controls, respectively). Results showed an increase in PiM2 allele frequencies in both patients' groups compared to controls. Allelic frequencies difference is significant only with the asthmatic group (p=0,0179). PiS and PiZ deficiency alleles are more prevalent in the emphysema (0.0298, 0.0149) than in the asthmatic subjects (0.0104, 0.0052). Meanwhile, no significant difference in PiS and PiZ allelic frequencies was observed between patients and controls. CONCLUSION: PiM2 allele can be considered as genetic risk factor for asthma. PiS and PiZ alleles are very rare in Tunisia in comparison with the European population, leading to a very small contribution in pulmonary diseases pathogenesis in Tunisia.


Assuntos
Asma/genética , Enfisema/genética , Polimorfismo Genético , alfa 1-Antitripsina/genética , Humanos , Tunísia
10.
Pathol Biol (Paris) ; 56(3): 106-10, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18031952

RESUMO

OBJECTIVES: The study investigated alpha 1 antitrypsin (AAT) gene polymorphism in the Tunisian population. We aimed to analyze the correlation between Pi polymorphism and the risk of developing chronic obstructive pulmonary disease (COPD). PATIENTS AND METHODS: We focused our study on two samples originating from the Tunisian centre: 318 healthy controls and 90 patients suffering from COPD. Data analysis was investigated by AAT level quantification, serum isoelectric focusing (IEF) and RFLP-PCR performed with PiS and PiZ allele specific primers. RESULTS: We calculated PiM1, PiM2, PiM3, PiS and PiZ allele frequencies in patients and controls. The difference in allele frequencies is significant only for the PiM2 allele (P=0.00378). In COPD patients, we note the presence of PiZ allele. This allele mainly observed in European populations, is rare in sub-Saharian populations and not described in North Africa. CONCLUSION: PiZ allele is found in COPD sample and never in Tunisian controls. However, no significant difference in PiZ allele frequency between patients and controls can be concluded. PiM2 allele, which is considered as "normal" variant can be associated with COPD risk.


Assuntos
Doença Pulmonar Obstrutiva Crônica/genética , alfa 1-Antitripsina/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Valores de Referência , Fumar , Tunísia
11.
Ann Biol Clin (Paris) ; 65(3): 251-6, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17502296

RESUMO

We analysed the C3*S and C3*F polymorphism of the third component of the complement (C3), first at the protein level by the electrophoresis of the plasma on agarose gel and second on the gene level by the ARMS PCR technique. We determined the phenotypic and genotypic frequencies of the C3 on a sample of 90 patients suffering from the obstructive chronic bronchopneumopathy (OCBP) disease. Comparisons have been done with frequencies observed on a control sample of 437 healthy individuals from the Tunisian population in order to establish a putative correlation between the polymorphism studied and the disease. Frequencies of the C3*S and C3*F alleles in OCBP patients are 0,788 and 0,212 respectively. They are not significantly different from those observed in control sample (0,834 and 0,152 respectively). Therefore, no correlation is observed between the C3 polymorphism and the risk of developing the OCBP disease.


Assuntos
Complemento C3/genética , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica/genética , Humanos , Tunísia
12.
Ann Biol Clin (Paris) ; 65(1): 59-63, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17264040

RESUMO

Mucopolysaccharidosis type IV A (MPS IV A) is an autosomal recessive disorder resulting from the deficient activity of the lysosomal enzyme, N-acetylgalactosamine-6-sulfate sulfatase (GALNS) and the progressive lysosomal accumulation of keratane sulfate. Clinically, the MPS IV A differs from the other MPS by the localisation of the keratane sulfate in skelet and in eyes associated to the conservation of a normal intelligence. To date, the characterization and purification of the GALNS gene made a research for pathogenic mutations in patients with MPS IV A easier. These mutations are responsible of severe, intermediate or mild phenotype. The aim for this work was the research of clinical, biologic and molecular characteristics of two Tunisian MPS IV A patients who were offsprings of consanguineous mating. Enzymatic and urinary diagnostics suggested a MPS IV A phenotype. A novel homozygous mutation IVS1+1G-A was identified by direct sequencing in the GALNS gene of the two patients. Identification of GALNS mutations provide genotype/phenotype correlations and permit the precision of anomalies responsible of Morquio A phenotype in concerned families.


Assuntos
Condroitina Sulfatases/genética , Mucopolissacaridoses/genética , Adolescente , Consanguinidade , Feminino , Genótipo , Humanos , Masculino , Mutação , Fenótipo , Análise de Sequência de DNA , Irmãos , Tunísia
14.
Ann Biol Clin (Paris) ; 61(2): 229-33, 2003.
Artigo em Francês | MEDLINE | ID: mdl-12702481

RESUMO

At present, the application of combined methods in molecular biology allows us to carry out the prenatal diagnosis in a more rapid and less onerous manner especially when the family presents an index case. In this study, we have analyzed a family with one case of intermediate beta-thalassemia. First, we have used the denaturing gradient gel electrophoresis (DGGE). Then, we have identified the mutations by the refractory mutation system technique (ARMS PCR) using specific primers for the most frequent mutations in the Tunisian population (codon 39 (C --> T) and IVS-I-2 (T--> G) for beta0 thalassemias and IVS-I-110 (G --> A) for beta+ thalassemias). The analyzed family has shown the IVS-I-110 (G --> A) mutation in the heterozygous state in the mother and the index case. Subsequently, sequencing in the gene revealed a frameshift 8 (-AA) mutation in the father and his daughter. This patient is thus a compound heterozygote Codon 8 (-AA)/IVS-I-110. DGGE and ARMS PCR analysis of foetal DNA extracted from trophoblast culture didn't show any of the two mutations found in the family.


Assuntos
Mutação , Diagnóstico Pré-Natal , Talassemia beta/diagnóstico , Talassemia beta/genética , Adulto , Sequência de Bases , Criança , Códon , Eletroforese em Gel de Poliacrilamida , Feminino , Genótipo , Heterozigoto , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Gravidez , Tunísia
15.
Ann Biol Clin (Paris) ; 58(4): 453-60, 2000.
Artigo em Francês | MEDLINE | ID: mdl-10932046

RESUMO

Beta-thalassemia, by its high frequency and its heterogeneity, constitutes a real problem of health in Tunisia. Prenatal diagnosis by DNA analysis represents the only reality for couples at risk. The denaturant gradient (urea and formamide) on polyacrylamide gel electrophoresis has been performed in our laboratory, using psoralen as chemical clamps. This method is simple, reliable, safe, rapid, without radioactivity and has a reasonable cost (chemical clamps). Even if it needs an informatic modelization in other laboratories, this method seems to be adapted to our economic and work conditions and to the molecular heterogeneity of the Tunisian beta-thalassemia. We present the results of an epidemiological molecular study on 75 patients with beta-thalassemia and the results of ten prenatal diagnosis. The molecular lesions codon 39 (C-T) and IVS1 nt2 (T-G) are the most frequent in our study. This technical approach provides genetic counselling for at risk families by offering prenatal diagnosis (reducing as possible the cost and the delay of the result) after prealable family study and identification of the mutation(s).


Assuntos
Globinas/genética , Mutação , Diagnóstico Pré-Natal , Talassemia beta/diagnóstico , Talassemia beta/embriologia , Códon , Feminino , Heterozigoto , Homozigoto , Humanos , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Gravidez , Tunísia/epidemiologia , Talassemia beta/epidemiologia , Talassemia beta/genética
16.
Hum Genet ; 99(5): 648-52, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9150734

RESUMO

The testis-determining gene SRY (sex determining region, Y) is located on the short arm of the Y chromosome and consists of a single exon, the central third of which is predicted to encode a conserved motif with DNA binding/bending properties. We describe the screening of 26 patients who presented with 46,XY partial or complete gonadal dysgenesis for mutations in both the SRY open reading frame (ORF) and in 3.8 kb of Y-specific flanking sequences. DNA samples were screened by using the fluorescence-assisted mismatch analysis (FAMA) method. In two patients, de novo mutations causing complete gonadal dysgenesis were detected in the SRY ORF. One was a nonsense mutation 5' to the HMG box, whereas the other was a missense substitution located at the C terminus of the conserved motif and identical to one previously detected in an unrelated patient. In addition, two Y-specific polymorphisms were found 5' to the SRY gene, and a sequence variant was identified 3' to the SRY polyadenylation site. No duplications of the DSS region in 20 of these patients were detected.


Assuntos
Proteínas de Ligação a DNA/genética , Disgenesia Gonadal/genética , Proteínas Nucleares , Fatores de Transcrição , Cromossomo Y , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Sequência Conservada , Primers do DNA , Éxons , Feminino , Marcadores Genéticos , Humanos , Masculino , Fases de Leitura Aberta , Mutação Puntual , Reação em Cadeia da Polimerase , Proteína da Região Y Determinante do Sexo , Testículo , Cromossomo X
17.
Ann Biol Clin (Paris) ; 49(7): 389-96, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1684890

RESUMO

48 Tunisian people suffering from the IDDM auto-immune disease were compared to 35 control healthy persons for the polymorphisms of the complement BF, C2 and C4 proteins and genes, of the IgG (Gm allotypes) as well as of the TNF alpha and TCR C beta genes. Our study shows that the BFF1-C4A3-C4BQO and BFS-C4AQ0-C4B1 complotypes are associated to IDDM (RR of 2.97 and 3.07 respectively), as previously reported for other circummediterranean populations. The frequency of the Gm 21.28; 1.17; .. haplotype is increased, but not significantly, among the patients. The RFLP analysis reveals that the 2.65 kb SacI allelic restriction fragment of the C2 gene may be considered as a genetic marker of susceptibility to IDDM because its frequency raises to 0.206 among the patients vs 0.021 in the healthy individuals (p less than 0.001). The frequencies of the C4AQ0 and C4BQ0 alleles are more important among the IDDM patients than within the control sample, but the only C4BQ0 allele frequency is significantly increased. Both C4AQ0 and C4BQO result mainly from deletions. The frequencies of the allelic restriction fragments of the TNF alpha and TCRC beta genes are not significantly different among the patients and the controls. But the small sample size don't allow us to conclude definitively. It would be very interesting to extend the RFLP analysis to the TCR V beta and V alpha gene regions on more numerous samples.


Assuntos
Diabetes Mellitus Tipo 1/genética , Marcadores Genéticos , Adolescente , Adulto , Criança , Complemento C2/genética , Complemento C4/genética , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Imunogenética , Imunoglobulinas/genética , Complexo Principal de Histocompatibilidade/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Esteroide 21-Hidroxilase/genética , Fator de Necrose Tumoral alfa/genética , Tunísia
19.
Proc Natl Acad Sci U S A ; 86(3): 1041-5, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2915972

RESUMO

We have characterized a Mediterranean beta-thalassemia allele containing a sequence change at codon 30 that alters both beta-globin pre-mRNA splicing and the structure of the hemoglobin product. Presumably, this G----C transversion at position -1 of intron 1 reduces severely the utilization of the normal 5' splice site since the level of the Arg----Thr mutant hemoglobin (designated hemoglobin Kairouan) found in the erythrocytes of the patient is very low (2% of total hemoglobin). Since no natural mutations of the guanine located at position -1 of the CAG/GTAAGT consensus sequence had been isolated previously, we investigated the role of this nucleotide in the constitution of an active 5' splice site by studying the splicing of the pre-mRNA in cell-free extracts. We demonstrate that correct splicing of the mutant pre-mRNA is 98% inhibited. Our results provide further insights into the mechanisms of pre-mRNA maturation by revealing that the last residue of the exon plays a role at least equivalent to that of the intron residue at position +5.


Assuntos
Éxons , Genes , Globinas/genética , Mutação , Precursores de RNA/genética , Splicing de RNA , Talassemia/genética , Adulto , Sequência de Bases , Clonagem Molecular , Citosina , Feminino , Genótipo , Guanina , Humanos , Dados de Sequência Molecular , Fenótipo , Valores de Referência , Talassemia/sangue
20.
Hum Genet ; 78(2): 190-2, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3422218

RESUMO

We have determined the spectrum of mutations producing beta-thalassemia (beta-thal) in Tunisia by direct DNA analysis using hybridization with allele-specific oligonucleotide probes and restriction endonuclease assay. In all, 34 unrelated beta-thal patients originating from different parts of the country were available for study. The beta-globin gene cluster of each was subjected to haplotype analysis, and on the basis of this analysis, we tested each patient's DNA for one or more mutations previously shown to be linked to that haplotype. We identified four previously unreported haplotypes and found that this population differs from others in Mediterranean areas in the frequency of the beta-thal haplotypes, the unexpected observation being the high frequency of haplotype IX. Six different point mutations were found, accounting for 62% of beta-thal genes in this Tunisian population. The molecular defects known to be the most frequent in Mediterraneans (nonsense codon 39, IVS1 nt 110, IVS1 nt 6) only make up 37% of the mutant genes. One as yet undescribed mutation (IVS1 nt 2 T----G) was identified by molecular cloning and sequencing. Our results should help the implementation of a prenatal diagnosis program for beta-thal in Tunisia.


Assuntos
Globinas/genética , Mutação , Talassemia/genética , Marcadores Genéticos , Humanos , Tunísia
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