TANC1 is a scaffold protein containing tetratricopeptide, ankyrin, and coiled-coil domains that functions primarily in synaptic regulation and myoblast biology. In the nervous system, TANC1 acts as a postsynaptic density component regulating excitatory synapse strength and synaptic spine density 1. In muscle development, TANC1 is essential for myoblast fusion; its ectopic expression blocks myogenic differentiation while suppressing TANC1 restores both fusion and terminal differentiation 2. Disease relevance spans multiple pathologies. In rhabdomyosarcoma, the PAX-FOXO1 fusion oncoprotein upregulates TANC1 to block myoblast fusion and promote neoplastic transformation; reducing TANC1 expression reverses this phenotype 2. TANC1 variants are implicated in neurodevelopmental disorders as a candidate gene 1, with cancer-associated mutations dramatically decreasing protein solubility and stability 1. A TANC1::YY1AP1 fusion has been identified in salivary gland intraductal carcinoma 3. Clinically, TANC1 genetic variants associate with late radiation-induced toxicity in prostate cancer patients 4, likely reflecting its role in muscle regeneration and repair. TANC1 methylation serves as a diagnostic biomarker for anti-tuberculosis drug-induced liver injury 5. TANC1 genetic profiling may inform personalized radiotherapy strategies, particularly in indigenous populations 6.