FOXP3 genetic variants are associated with asthma severity in Brazilian women.

The aim of this study was to verify the associations between variants in FOXP3, with different asthma phenotypes and the expression of this molecule in CD4 + CD25 hi FOXP3 + T lymphocytes. DNA was extracted from the peripheral blood of the 1,418 individuals recruited in to ProAR, case-control study in Salvador, Brazil. The SNPs included in FOXP3 (rs2280883, rs2294021, rs3761548, rs2232365) were genotyped using the TaqMan probe. Analyzes for genetic associations were performed by logistic regressions using PLINK 1.9 software for men and women, separately, and adjusted for age and skin color. The expression of FOXP3 in CD4 + CD25 hi FOXP3 + T lymphocytes was determined in a sub-sample by cytometry and evaluated according to the genotypes in the Graphpad software. Analyzing the association in women, only rs2294021 was positively associated with asthma, mild asthma and severe asthma when compared to controls. The rs2232365 was negatively associated with irreversible asthma. In men, there was no significant association. The expression of FOXP3 in CD4 + CD25 hi FOXP3 + T lymphocytes was significant only for rs2232365 in TT individuals when compared to CT (* p