More recently, four genome wide association studies (GWAS) which included North American, Italian, predominantly North American, and British cohorts, respectively, identified a number of genes in non-HLA loci associated with PBC and highlighted the role of the IL-12 and tumor necrosis factor (TNF) signaling pathways in the pathogenesis of PBC [23–26]. This evidence concerns the gene TNF and primary biliary cholangitis.