In this study, we examined the histological changes in mice reflux modes using additional immunohistochemical stainings of CDX2, PDX1, and CK7, because CDX2 is a homeobox domain-containing transcription factor that is important in the development and differentiation of the intestines and it is widely accepted that CDX2 plays key roles on differentiation into the intestinal-type cell characteristic of Barrett’s esophagus [7, 8]. The gene discussed is KRT7; the disease is esophageal adenocarcinoma.