RESUMO
The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.
Assuntos
Doenças Autoimunes/genética , Genes rel , Interleucina-2/genética , Vitiligo/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Adulto , Idade de Início , Doenças Autoimunes/complicações , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Humanos , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Vitiligo/complicações , Adulto JovemRESUMO
The hemorrhagic diseases are characterized by bleeding which can vary considerably according to their severity. The von Willebrand disease (VWD) is the most frequent hereditary hemorrhagic disease and the prevalence of clinically significant disease is probably closer to 1:1000, being an extremely heterogeneous and complex disorder that is related to the deficiency in concentration, structure or function of von Willebrand factor (VWF). The VWD is divided into type 1, with partial deficiency of the VWF, type 2, with qualitative defects in the molecule with four subdivisions, and type 3, with very low or undetectable levels of plasma and platelet VWF and ristocetin cofactor activity. The laboratory diagnosis of VWD is complex. Specific tests that assess the functionality and concentrations of the VWF and FVIII are needed. The routine tests are the bleeding time, the activated partial thromboplastin time and the platelet count, however, singly, they may not suggest the diagnosis of VWD, requiring further specific tests, such as VWF function evaluation through its ristocetin cofactor assay (VWF:RCo), VWF protein concentration immunoassay (VWF:Ag), the factor VIII coagulation assay ( FVIII: C), VWF binding to immobilized collagen (VWF:CB), ristocetin-induced platelet aggregation (RIPA), VWF multimers patterns, factor VIII binding of immobilized VWF (VWF:FVIIIB), among others. From the moment the diagnosis is confirmed, the appropriate treatment for each patient is sought, with the purpose of increasing plasma concentrations of the deficient protein, both in bleeding episodes, as for invasive procedures. Although diagnosis facilitates treatment other approach in the present scenario is prenatal diagnosis which, is the need of the hour.
RESUMO
Diabetes mellitus is a public health problem, which affects a millions worldwide. Most diabetes cases are classified as type 2 diabetes mellitus, which is highly associated with obesity. Type 2 diabetes is considered a multifactorial disorder, with both environmental and genetic factors contributing to its development. An important issue linked with diabetes development is the failure of the insulin releasing mechanism involving abnormal activity of the ATP-dependent potassium channel, KATP. This channel is a transmembrane protein encoded by the KCNJ11 and ABCC8 genes. Furthermore, polymorphisms in these genes have been linked to type 2 diabetes because of the role of KATP in insulin release. While several genetic variations have been reported to be associated with this disease, the E23K polymorphism is most commonly associated with this pathology, as well as to obesity. Here, we review the molecular genetics of the potassium channel and discusses its most described polymorphisms and their associations with type 2 diabetes mellitus.
Assuntos
Trifosfato de Adenosina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Canais de Potássio/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Humanos , Polimorfismo Genético/genética , Canais de Potássio/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Receptores de Sulfonilureias/genética , Receptores de Sulfonilureias/metabolismoRESUMO
OBJECTIVE: To investigate the association of the rs10885122G>T polymorphism in the ADRA2A gene in a Euro-Brazilian sample of healthy (controls) and type 2 diabetic (T2D) subjects. SUBJECTS AND METHODS: We used fluorescent probes (TaqMan) to genotype 241 subjects, that is, 121 healthy and 120 T2D subjects, who were classified based on the Brazilian Diabetes Association (2013) and American Diabetes Association (2014) criteria. RESULTS: The genotype and allele frequencies showed no significant (P > 0.05) difference between the two studied groups. The minor allele (T) frequencies (95%CI) for rs10885122 were 19% (14-24%) and 20% (15-26%) for healthy and T2D groups, respectively. Carriers of the T allele (genotypes GT+TT) were significantly associated (P = 0.016) with approximately a 7-kg body weight reduction compared with the genotype GG, which was only found in the T2D group. CONCLUSION: The rs10885122G>T polymorphism of the ADRA2A gene was not associated with T2D in Euro-Brazilians, and carriers of the T allele had lower body weight in the presence of T2D.
Assuntos
Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético , Receptores Adrenérgicos alfa 2/genética , População Branca/genética , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , População Branca/etnologiaRESUMO
OBJECTIVE: To investigate the association between fat mass and obesity-associated (FTO) gene polymorphisms rs8050136C>A and rs9939609T>A, and transcription factor 7-like 2 (TCF7L2) gene polymorphisms rs12255372G>T and rs7903146C>T, in a sample group of pregnant Euro-Brazilian women with or without gestational diabetes mellitus (GDM). METHODS: Subjects were classified as either healthy pregnant control (n=200) or GDM (n=200) according to the 2010 criteria of the American Diabetes Association. The polymorphisms were genotyped using fluorescent probes (TaqMan®). RESULTS: All groups were in the Hardy-Weinberg equilibrium. The genotype and allele frequencies of the examined polymorphisms did not exhibit significant difference (P>0.05) between the groups. In the healthy and GDM pregnant women groups, the A-allele frequencies (95% CI) of FTO polymorphisms rs8050136 and rs9939609 were 39% (34-44%); 38% (33-43%) and 40% (35-45%); 41% (36-46%), respectively; and the T-allele frequencies of TCF7L2 polymorphisms rs12255372 and rs7903146 were 30% (26-35%), 32% (27-37%) and 29% (25-34%), 36% (31-41%), respectively. CONCLUSION: The examined polymorphisms were not associated with GDM in the Euro-Brazilian population studied.
Assuntos
Diabetes Gestacional/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , População Branca/genética , Adulto , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Brasil , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Gravidez , Adulto JovemRESUMO
Objective To investigate the association of the rs10885122G>T polymorphism in the ADRA2A gene in a Euro-Brazilian sample of healthy (controls) and type 2 diabetic (T2D) subjects. Subjects and methods We used fluorescent probes (TaqMan) to genotype 241 subjects, that is, 121 healthy and 120 T2D subjects, who were classified based on the Brazilian Diabetes Association (2013) and American Diabetes Association (2014) criteria. Results The genotype and allele frequencies showed no significant (P > 0.05) difference between the two studied groups. The minor allele (T) frequencies (95%CI) for rs10885122 were 19% (14-24%) and 20% (15-26%) for healthy and T2D groups, respectively. Carriers of the T allele (genotypes GT+TT) were significantly associated (P = 0.016) with approximately a 7-kg body weight reduction compared with the genotype GG, which was only found in the T2D group. Conclusion The rs10885122G>T polymorphism of the ADRA2A gene was not associated with T2D in Euro-Brazilians, and carriers of the T allele had lower body weight in the presence of T2D. Arch Endocrinol Metab. 2015;59(1):29-33 .