Sdhb, also known as succinate dehydrogenase B, is a mitochondrial gene that is related to the metabolic activities of cells and tissues throughout the body [3]. It is a subunit of succinate dehydrogenase, which is involved in the tricarboxylic acid cycle and oxidative phosphorylation pathways [3]. These pathways are crucial for energy production in cells.

Carriers of germline pathogenic variants in Sdhb are at increased risk of developing pheochromocytomas and paragangliomas (PPGLs) [1]. The penetrance of PPGLs in Sdhb pathogenic variant carriers increases linearly with age, and affected carriers are at risk of developing and dying of metastatic disease or developing second tumors [1]. SDHB-associated pheochromocytomas are often unilateral, and associated with advanced and recalcitrant disease, often being metaidobenzyleguanidine (MIBG) positive [2]. Also, SDHB immunohistochemistry can be used as a prognostic biomarker for pheochromocytoma and paraganglioma patients, with SDHB (-) staining indicating a poorer prognosis [4].

In conclusion, Sdhb is essential for normal cellular metabolic activities through its role in key energy-related pathways. The study of Sdhb using genetic models helps to understand its role in the development and progression of diseases such as pheochromocytomas and paragangliomas. Understanding the functions of Sdhb can potentially provide new insights into the diagnosis, prognosis, and treatment of these related diseases.