Another subgroup of KIT/PDGFRA wild-type GIST with intact SDH complex, collectively defined as RAS-pathway (RAS-P)-mutant GIST, includes patients that either carry inactivating mutations in NF1 gene, often signaling an unrecognized NF1 syndromic condition (10, 11), or activating mutations in BRAF or more rarely a RAS gene (12, 13). The gene discussed is SDHB; the disease is gastrointestinal stromal tumor.