SDH deficient (dSDH) wtGIST is the most common subcategory of wtGIST [9], and these tumours are driven by inherited germline mutations in one of the SDHx genes (SDHA/B/C/D) [9] or can occur sporadically following epigenetic silencing of the SDHC gene [10]. The gene discussed is SDHC; the disease is neoplasm.