Intestinal fibrosis is one of the most common complications of IBD which affects more than 30% of patients, and is usually defined as the excessive accumulation of scar tissue in the intestinal wall.[54] Scar tissue formation is induced by the chronic inflammation that promotes the proliferation and collagen secretion of the fibroblasts.[54] Specifically, TNF‐alpha and other inflammatory cytokines can enhance the proliferation of myofibroblasts and smooth muscle cells, which leads to excessive collagen deposition. The gene discussed is TNF; the disease is inflammatory bowel disease.