Rinsho Shinkeigaku (Clinical Neurology)

Symposium 2

Myofibrillar myopaathy

Yukiko Hayashi, M.D., Ph.D.1)

1)Department of Neurophysiology, Tokyo Medical University

Myofibrillar myopathy (MFM) is a group of hereditary disorders pathologically characterized by focal disorganizations of myofibril structures with cytoplasmic inclusions. Most of the diseases so-called desmin-related or storage myopathy, cytoplasmic body myopathy, spheroid body myopathy, reducing body myopathy, and hyaline body myopathy are included in MFM. Several causative genes have been identified such as DES, CRYAB, MYOT, ZASP, BAG3, FLNC, DNAJB6, FHL1, TTN, and VCP. Most of these genes encode Z-line related proteins or proteins associated with protein quality control. Since MFM is the name from pathological characteristics, clinical features of the patients including the age at disease onset, affected muscles, disease course, and complications are quite variable. In this paper, characteristic clinical and pathological features of each causative gene are summarized. Unexpectedly, hereditary myopathy with early respiratory failure (HMERF) caused by mutation in the A-band region of TTN is the most common cause of MFM in our cohort. Despite of intensive mutation screening, the causative gene of more than 60% of MFM patients is still unknown. Further identification of novel causative genes and elucidate pathomechanisms of protein aggregation in necessary.
Full Text of this Article in Japanese PDF (2948K)

(CLINICA NEUROL, 53: 1105|1108, 2013)
key words: disorganized myofibrils, cytoplasmic inclusion, sarcomere, Z-line, protein aggregation

(Received: 30-May-13)