A set of clinically and genetically heterogeneous disorders characterized by abnormal thread- or rod-like (nemaline) structures (nemaline bodies) in muscle and progressive muscle weakening. All are due to defects in genes encoding muscle proteins. The mutation in NEM1 is in tropomyosin-3, in NEM2 (the commonest form) in nebulin, in NEM3 in α-actin-1, in NEM4 in β-tropomyosin, in NEM5 (Amish nemaline myopathy) in troponin T1, in NEM7 in cofilin-2. Loci for other forms have been identified.
Subjects: Medicine and Health — Chemistry.