In addition, the genotype TT of XRCC4 rs1056503 showed significant association with increased susceptibility of HIV-1 infection in the codominant model (TT vs. GG, P = 0.035, OR = 1.698, 95% CI: 1.037-2.779) and recessive model (TT vs. TG+GG, P = 0.028, OR = 1.707, 95% CI: 1.060-2.750). This evidence concerns the gene XRCC4 and HIV-1 infection.