Gene mutations haveemerged in many inherited cancer syndromes, which lead to GC occurrence such as the loss of one allele of Cadherin 1(CDH1) gene, which normally encodes E-cadherin, an adhesion molecule [27,28], resulting in HDGC, a dominant autosomal syndrome that promotes not only cancer cell growth beneath the gastric epithelium but also colorectal cancer and extra-gastrointestinal malignancies [27,29]. Here, CDH1 is linked to Down syndrome.