In order to apply this technique to candidate genes studies associated with autoimmune and infectious diseases, we developed a multiplex assay designed to genotype 16 single nucleotide polymorphisms (SNPs) among nine genes of the innate immune system: IL1α, IL1β, IL6, IL10, IL12RB1, TLR2, TLR4, TLR9 and CD14. Here, IL12RB1 is linked to infectious disease.