Genetic association studies have identified not only hundreds of susceptibility loci to immune-mediated diseases but also pinpointed causal amino-acid variants of HLA genes that contribute to many autoimmune reactions. Majority of non-HLA genetic variants are located within non-coding regulatory region. Expression QTL studies have shown that these variants affect disease mainly by regulating gene expression. We discuss recent findings on shared genetic loci between infectious and immune-mediated diseases and provide potential clues to explore genetic associations in the context of these infectious agents. We propose that the interdisciplinary studies (genetics genomics immunology infection bioinformatics) are the future post-GWAS approaches to advance our understanding of the pathogenesis of immune-mediated diseases.