One of the molecular characteristics of these neoplasms is a gain of function mutation in the receptor tyrosine- kinase protein (KIT) (75-80% of cases) or the homologous receptor tyrosine kinase, platelet-derived growth factor receptor alpha (PDGFRA), accounting for 85-90% of gastrointestinal stromal tumors [2]. The gene discussed is KIT; the disease is gastrointestinal stromal tumor.