Gene SDHB
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Also known as
Succinate Dehydrogenase Complex Iron Sulfur Subunit B, CWS2, IP, PGL4, SDH, SDH1, SDHIPOverview
SDHB (Succinate Dehydrogenase Complex Iron Sulfur Subunit B) encodes one of four subunits that make up the succinate dehydrogenase (SDH) complex, also known as mitochondrial complex II. This enzyme complex serves a dual function in cellular metabolism: it participates in both the citric acid cycle (Krebs cycle) by catalyzing the oxidation of succinate to fumarate, and in the electron transport chain by transferring electrons to ubiquinone. The SDHB subunit contains iron-sulfur clusters essential for electron transfer and is anchored to the inner mitochondrial membrane.Germline mutations in SDHB are associated with hereditary paraganglioma-pheochromocytoma syndrome, characterized by the development of paragangliomas (tumors of the autonomic nervous system) and pheochromocytomas (adrenal gland tumors that produce catecholamines). SDHB mutations are particularly associated with extra-adrenal paragangliomas, malignant transformation, and metastatic disease, making SDHB-related tumors among the most aggressive in the SDH-related tumor spectrum. Affected individuals may also have increased risks of renal cell carcinoma and gastrointestinal stromal tumors. Genetic testing for SDHB mutations is crucial for early tumor detection through surveillance imaging, surgical planning, and genetic counseling for family members at risk.