Through in vitro infection of peripheral blood mononuclear cells, which were isolated from healthy donors, with a CCR5-tropic HIV isolate, Salkowitz et al. [8] showed that −2459G > A was associated with CCR5 expression as well as the magnitude of HIV-1 propagation: low, medium, and high levels of viral propagation were associated with G/G, G/A, and A/A promoter genotypes, respectively. Here, CCR5 is linked to infection.