CD4 and chlamydia trachomatis infectious disease: Since rs112651494 and rs617058 are found in the intronic and the intergenic regions, respectively, and do not code for any amino acids, it would be interesting to elucidate whether these variants have any regulatory effects at the transcriptional level that can affect the binding of chlamydial antigens to the HLA class II molecules and, in turn, modify the activation of CD4+ T cells which are important for protection against chlamydia reinfection.