MYH11 (Myosin Heavy Chain 11): MYH11 is a gene that encodes a smooth muscle myosin heavy chain, a crucial component of the contractile machinery in smooth muscle cells. This protein is essential for smooth muscle contraction and relaxation, supporting key functions such as vascular regulation, gastrointestinal motility, and respiratory activity. MYH11 helps maintain the structure and function of smooth muscle tissues throughout the body. Alterations or mutations in this gene can contribute to vascular disorders, including thoracic aortic aneurysms and dissections.