Of these tumours, SDH-deficient (characterized by the loss of SDHB) and quadruple WT GIST (KIT/PDGFRA/SDH/RAS-P WT) subgroups were reported to display a marked overexpression of FGF4, identifying a putative common therapeutic target for the first time. The gene discussed is SDHB; the disease is gastrointestinal stromal tumor.