Gastrokine 1 (GKN1),a stomach-specic protein also known as 18 kDa antrum mucosa protein (AMP-18) or foveolin,belongs to the gastrokine family of gastric mucus cell-secreted proteins. The human GKN1 gene has been localized in a region of chromosome 2p13 of about 6 kb and contains 6 exons. GKN1 is expressed only in normal human stomach,but is absent from gastric adenocarcinomas,gastro-esophageal adenocarcinoma cell lines,and other normal and tumor gastro-intestinal tissues. GKN1may play an important role in normal gastric function and may be a gastric tumour suppressor.
