Recently, many studies [13, 21–30] have described the associations between MDM4 gene polymorphisms and risks of various cancers, including colon cancer, lung cancer, breast cancer, gastric cancer, squamous cell carcinoma of the head and neck, non-Hodgkin lymphoma (NHL), and esophageal squamous cell carcinoma (ESCC). The gene discussed is MDM4; the disease is breast carcinoma.