RESUMO
Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that regulates innate and adaptative immunity responses against pathogens. The MIF gene, at 22q11.2, is polymorphic. Functional promoter variants in the MIF gene influence susceptibility to inflammatory diseases in Caucasians and Africans. An association study was carried out to examine the influence of MIF-173 single nucleotide polymorphism and the MIF-794 microsatellite on the susceptibility to develop human tuberculosis (TB) in a well-defined Latin-American population. To this purpose, 230 northwestern Colombian patients with pulmonary TB, negative for human immunodeficiency virus infection, and 235 matched healthy individuals stratified by the tuberculin skin test were examined. Multivariate analysis showed that MIF-173C allele was associated with disease (odds ratio = 1.64, 95% confidence interval 1.07-2.52) in a dominant pattern. No allele in the MIF-794 CATT microsatellite was associated with risk of TB. These results indicate that MIF gene influences the risk of developing TB in the studied population.
Assuntos
Fatores Inibidores da Migração de Macrófagos/genética , Tuberculose Pulmonar/genética , Alelos , Estudos de Casos e Controles , Cromossomos Humanos Par 22 , Colômbia/epidemiologia , Intervalos de Confiança , Feminino , Predisposição Genética para Doença , Geografia , Humanos , Fatores Inibidores da Migração de Macrófagos/sangue , Masculino , Repetições de Microssatélites , Razão de Chances , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/genética , Fatores de Risco , Teste Tuberculínico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/imunologiaRESUMO
The purpose of the present study was to address the possible contribution of the (CCTTT)n microsatellite polymorphism in the NOS2 promoter region to the susceptibility to chronic Trypanosoma cruzi infection and to Chagas' disease related cardiomyopathy. We determined the (CCTTT)n genotypes in a sample of 76 serologically positive chagasic individuals and in 78 healthy controls. No statistically significant differences were observed between total chagasic patients and healthy controls with regard to frequency of the (CCTTT)n microsatellite repeat of any given length. Likewise, we found no differences in the distribution of the (CCTTT)n microsatellite repeats between seropositives without manifestations of the disease and those with chagasic cardiomyopathy. Our data suggest that the NOS2 promoter pentanucleotide microsatellite polymorphisms analyzed do not play a major role in the pathogenesis of chronic T. cruzi infection in this Peruvian sample.
Assuntos
Doença de Chagas/genética , Óxido Nítrico Sintase/genética , Polimorfismo Genético , Trypanosoma cruzi , Animais , Doença de Chagas/metabolismo , Suscetibilidade a Doenças , Humanos , Repetições de Microssatélites , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Peru , Regiões Promotoras Genéticas/genéticaRESUMO
The distribution of HLA-A, -B, -C, -DRB1 and -DQB1 alleles in the Peruvian population was studied and compared with those of other populations in order to provide further information about their anthropological origin. Our data are consistent with the Mestizo character of this population. In terms of genetic distance Peruvians are closest to Bolivians, which is in agreement with the geographical location and the cultural and anthropological background of the two human groups. Several HLA-B alleles originally described in genetically isolated Amerindian tribes are also present in the sample studied here. This fact and the reported finding of these alleles in several Amerindian groups suggests that they were present in the first wave of humans that populated South America (Paleoindians) before they split to give rise to the different South American tribes.