GNAS and pancreatic intraductal papillary-mucinous neoplasm: Using a unique ligation assay, Wu et al. analyzed 132 IPMNs (113 IPMN tissue samples and 19 cyst fluids) and found that 66% of IPMNs harbored GNAS mutations, 81% harbored KRAS mutations, and 51% harbored both GNAS and KRAS mutations [65].