The large degree of linkage disequilibrium between different KIR genes, e.g., KIR2DL2 and KIR2DS2, and KIR2DS1 and KIR3DS1, however makes it hard to pinpoint a specific KIR/HLA class I interaction at the genetic level, as responsible for protection or susceptibility to a given infection. The gene discussed is KIR3DL1; the disease is infection.