NOD2 and tuberculosis: A number of immunity-related genes have been reportedly associated with susceptibility to TB among different populations, such as human leukocyte antigen (HLA), low molecular weight polypeptide/transporter with antigen processing, natural resistance-associated macrophage protein 1 (NRAMP1), dendritic cell-specific ICAM-3-grabbing non-integrin (DC-SIGN), Toll-like receptors (TLR) 1 and 2, vitamin D receptor (VDR), TNF, interleukin (IL) -1β, IL-6, IL-8, IL-10, interferon γ (IFN-γ), and nucleotide oligomerization binding domain 2 (NOD2) (2, 4, 6, 7).