Considering that sex [hazard ratio (HR) = 1.608, confidence interval (CI)95% 1.000-2.587, p = 0.050] and ethnicity (HR = 1.657, CI95% 1.054-2.606, p = 0.029) showed significance in Cox Regression Univariate test (Table III), and that HLA-B*57, HLA-B*27, and CCR5 del32 polymorphisms are well known factors that affect time to progress to AIDS, a multivariate stepwise Cox regression was performed. Here, CCR5 is linked to AIDS.