FHL1 (four and a half LIM domains 1) is an X-linked gene encoding a LIM domain protein that plays critical roles in muscle development and viral infection susceptibility. FHL1 mutations cause a spectrum of X-linked myopathies including Emery-Dreifuss muscular dystrophy type 6, reducing body myopathy, scapuloperoneal myopathy, and X-linked myopathy with postural muscle atrophy 12. These conditions are characterized by scapuloperoneal muscle weakness, rigid spine, cardiac involvement, and cytoplasmic bodies in muscle biopsies 2. The protein is highly expressed in muscle tissue and interacts with Z-line related proteins, contributing to myofibrillar organization 3. Beyond its structural role, FHL1 serves as a crucial host factor for chikungunya virus (CHIKV) infection by directly binding to the viral nsP3 protein's hypervariable domain, facilitating viral RNA replication 45. FHL1-deficient cells and mice show resistance to CHIKV infection and reduced disease pathology 45. Additionally, FHL1 has been identified as a potential autoantibody target in idiopathic inflammatory myopathies, associated with severe disease manifestations 6. The protein's dual role in muscle structure and viral susceptibility makes it clinically significant for both inherited myopathies and infectious disease outcomes.