Current treatment for IBD, which mainly involves anti-inflammatory drugs (e.g. mesalazine), corticosteroids (e.g. prednisone), immunosuppressant drugs (e.g. azathioprine), biological therapy [e.g. tumor necrosis factor α (TNF-α) inhibitors such as infliximab and adalimumab] and surgery, is costly and often associated with severe adverse effects (Baumgart and Sandborn, 2012; Ordás et al., 2012). The gene discussed is TNF; the disease is inflammatory bowel disease.