title: The IFN-gamma +874T/A gene polymorphism is associated with retinochoroiditis toxoplasmosis susceptibility.
abstract: Toxoplasmosis is a worldwide zoonosis that generally produces an asymptomatic infection. In some cases, however, toxoplasmosis infection can lead to ocular damage. The immune system has a crucial role in both the course of the infection and in the evolution of toxoplasmosis disease. In particular, IFN-gamma plays an important role in resistance to toxoplasmosis. Polymorphisms in genes encoding cytokines have been shown to have an association with susceptibility to parasitic diseases. The aim of this work was to analyse the occurrence of polymorphisms in the gene encoding IFN-gamma (+874T/A) among Toxoplasma gondii seropositive individuals, including those with ocular lesions caused by the parasite, from a rural population of Santa Rita de Cássia, Barra Mansa, state of Rio de Janeiro, Brazil. Further, we verified which of these polymorphisms could be related to susceptibility to the development of ocular toxoplasmosis. This study included 34 individuals with ocular toxoplasmosis (ocular group) and 134 without ocular lesions (control group). The differences between A and T allele distributions were not statistically significant between the two groups. However, we observed that a higher frequency of individuals from the ocular group possessed the A/A genotype, when compared with the control group, suggesting that homozygocity for the A allele could enhance susceptibility to ocular toxoplasmosis in T. gondii infection.
authors: Laboratório de Toxoplasmose, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil.
authors: Maíra Cavalcanti de
authors: MC
authors: Albuquerque
authors: Ana Luisa Quintella do Couto
authors: AL
authors: Aleixo
authors: Eliezer Israel
authors: EI
authors: Benchimol
authors: Ana Cristina Câmara S
authors: AC
authors: Leandro
authors: Leandro Batista
authors: LB
authors: das Neves
authors: Regiane Trigueiro
authors: RT
authors: Vicente
authors: Maria da Glória
authors: Mda G
authors: Bonecini-Almeida
authors: Maria Regina Reis
authors: MR
authors: Amendoeira
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002825:Chorioretinitis / Q000235:genetics / Q000276:immunology / Q000469:parasitology*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012424:Rural Population; D014126:Toxoplasmosis, Ocular / Q000235:genetics* / Q000276:immunology; D055815:Young Adult
chemical_list: D007371:Interferon-gamma