Abstract:

Mutations in the anoctamin 5 gene cause either limb girdle muscular dystrophy or Miyoshi muscular dystrophy 3 in Caucasians. We herein describe a 49-year-old Japanese man with asymmetry of the leg circumference since childhood. Muscle involvement began at the calf muscles, and later spread to the thigh and paraspinal muscles on imaging and physical examination. His external genitalia were morphologically hypoplastic. Genetic analysis identified a novel homozygous mutation, c.1178G>A (p.Trp393X), in the anoctamin 5 gene. This is the first Japanese case with Miyoshi muscular dystrophy 3 caused by an anoctamin 5 gene mutation (anoctaminopathy). The muscle impairment associated with Miyoshi muscular dystrophy 3 appears to spread from the distal to proximal lower extremities.

日本語要旨:

ANO5遺伝子変異による三好型筋ジストロフィー症例を本邦で初めて報告した。症例は49歳の日本人男性で、小児期から下肢周囲径に左右差があり、外性器低形成を認めた。身体診察および画像検査から、骨格筋障害は下腿筋から始まり、後に大腿や傍脊柱筋に広がることがわかった。