CD4 and AIDS: A possible role for these genetic markers in evaluation of AIDS risk was underscored by the observation that CCL3L1-CCR5 GRG status predicted HIV disease course independent of the viral load and CD4+ T cell count as well as other explanatory variables that were in themselves independent markers of disease progression (e.g., percent, nadir and cumulative CD4 cell counts, and DTH skin test reactivity) [20].