The National Institute of Neurological Disorders and Stroke (NINDS), the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), and the Muscular Dystrophy Association (MDA) invite applications focused upon determination of the mechanisms of a subset of muscular dystrophies that may have their basis in nucleus structure-function defects. Applications are specifically solicited for studies of Emery-Dreifuss, facioscapulohumeral, limb girdle muscular dystrophy 1B, and oculopharyngeal muscular dystrophies. Applications for studies of other muscular dystrophies are not responsive to this RFA. The expected outcomes are improvements in understanding of the genetic, cell, and molecular mechanisms of these muscular dystrophies. Applicants who can bring knowledge and expertise in the biology of the nucleus to studies of disease mechanisms are particularly encouraged.