According to their report, for common mutations in the biliary tract cancer, including gallbladder cancer, TP53, BRCA1, BRCA2, and PIK3CA were detected; for intrahepatic and extrahepatic duct-shared mutations, KRAS, SMAD4, ARID1A, and GNAS were detected. This evidence concerns the gene SMAD4 and biliary tract neoplasm.