Table 1. Pathways identified by IBD GWAS.

Genetic studies have identified a number of genes and pathways as potential players in the initiation and progression of IBD. Some of these pathways were previously known to be involved in IBD pathogenesis (left), while other pathways had been previously unknown (right).

Known IBD pathways confirmed by GWAS	Novel pathways implicated by GWAS
Barrier function	Autophagy
Role of T cell subsets	Regulation of IL23 signaling; Th17 development
Cytokine-cytokine receptor signaling	ROS signaling; IL1β
	CARD9, NOD2 in innate immunity
	Innate lymphoid cells
	Enrichment for genes implicated in immunodeficiencies
	Shared risk genes associated with susceptibility to Mycobacterium tuberculosis