Compared to ART initiation at 350–499 CD4+ T cells/mm3, initiation of ART at ≥500 cells/mm3 was found to be associated with decreased risk of developing AIDS-defining opportunistic infections in a pooled analysis of two non-overlapping studies: RR = 0.77 (95% CI 0.47–1.24) (22, 26) (Figure 4), there are no statistically significant effects (p = 0.28). This evidence concerns the gene CD4 and Opportunistic infection.