It has been reported that the homozygous recessive (TT) genotype of the TLR3 rs3775291 single-nucleotide polymorphism (SNP) provided resistance to HIV infection in Spanish HIV-exposed seronegative (HESN) intravenous drug users (IDUs), and individuals with this genotype sustained lower levels of viral replication [8]. The gene discussed is TLR3; the disease is HIV infectious disease.