Influência de polimorfismos de genes HLA na susceptibilidade ao dengue no sul do Brasil

Abstract

Dengue fever is a viral disease of most concern vectors transmitted by arthropods. Each year there is an estimated 50 to 100 million cases of dengue fever in the world. Besides environmental factors, genetic factors seem important in the manifestation of the disease, even in endemic areas because only a small proportion of people develop a more severe form. Immune response gene polymorphisms could be associated with the development of dengue cases. The purpose of this study was to determine the allele frequencies: HLA-A, B, Cw, DRB1, DQA1 and DQB1, in a population with dengue serology and confirmed by a population with symptoms but with negative serology, from Southern Brazil. A comparison of the frequencies of HLA alleles between these populations, by PCR-SSO genotyping based on Luminex technology, allowed determining association of HLA genes with protection and susceptibility to dengue in our region. There was negative association between HLA-A*31, A*69, A*31-B*40, B*40-Cw*03, B*58-Cw*07, DQA1*02-DQB1*03 and DQB1*0402/*0402, and dengue. HLA-A*66 was more frequent in patients than in controls, acting as a susceptibility gene for the disease. For HLA-A*31 and A*66, the values of P became not significant after Bonferroni´s correction. Thus, some HLA genetic factors were associated with classic dengue, serotype 3, in Southern Brazilian population.