Between 85 and 90% of gastrointestinal stromal tumours (GIST) harbour a mutation of v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) or platelet-derived growth factor receptor alpha (PDGFRa) [44], as potential LB markers Table 1. The gene discussed is PDGFRA; the disease is gastrointestinal stromal tumor.