ACVR1 is a gene that provides instructions for making a protein involved in the transforming growth factor-beta (TGF-β) signaling pathway. This pathway plays a crucial role in various cellular processes, including growth, differentiation, and development. Mutations in the ACVR1 gene can disrupt these processes and lead to various health issues. One notable condition associated with ACVR1 mutations is Fibrodysplasia Ossificans Progressiva (FOP), a rare genetic disorder characterized by the abnormal formation of bone in muscles and connective tissues. This condition can severely limit mobility and cause significant health challenges for affected individuals.