Gene RB1
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Also known as
Retinoblastoma 1, RB, p105-Rb, pRb, OSRCOverview
RB1 (Retinoblastoma 1) is a critical tumor suppressor gene that encodes the retinoblastoma protein (pRb), which plays a fundamental role in regulating the cell cycle and preventing uncontrolled cell division. The RB protein acts as a gatekeeper at the G1/S checkpoint, controlling the transition from the growth phase to DNA synthesis. It functions by binding to and inhibiting E2F transcription factors, which are necessary for the expression of genes required for cell cycle progression and DNA replication.Germline mutations in RB1 cause hereditary retinoblastoma, a rare eye cancer that primarily affects young children, typically before age 5. Individuals with hereditary RB1 mutations have a significantly increased risk of developing retinoblastoma in one or both eyes, as well as secondary cancers later in life, including osteosarcoma and soft tissue sarcomas. Somatic RB1 mutations are also commonly found in various adult cancers, including bladder cancer, small cell lung cancer, and breast cancer. Genetic testing for RB1 mutations is essential for early detection, surveillance, and family planning in affected families, as well as for understanding cancer risk and guiding treatment strategies.