Point mutations in the human ldb3 (ZASP) gene have been identified in patients with various myopathies such as dilated cardiomyopathy (DCM) [17], [32], left ventricular non-compaction (LVNC) [17], [32], hypertrophic cardiomyopathy [33] and inclusion body myositis [34] as well as in patients with an autosomal dominant form of progressive muscular dystrophy termed zaspopathy [35], [36]. The gene discussed is LDB3; the disease is myofibrillar myopathy 4.