A novel de novo mutation of the mitochondrial tRNA(lys) gene mt.8340G > A associated with pure myopathy

作者：Jeppesen Tina Dysgaard^*; Duno Morten; Risom Lotte; Wibrand Flemming; Rafiq Jabin; Krag Thomas; Jakobsen Johannes; Andersen Henning; Vissing John

来源：Neuromuscular Disorders, 2014, 24(2): 162-166.

DOI：10.1016/j.nmd.2013.08.004

• Novel mutation
• Mitochondrial DNA
• MTTK gene
• tRNA(lys)

Most patients with mutations in the tRNA(lys) gene (MTTK) present with symptoms from the central nervous system (CNS). We describe a 41-year-old woman with pure myopathy associated with a novel de novo mtDNA mutation, mt.8340G>A, which was heteroplasmic in muscle (53%), blood, urine and mouth epithelial cells (<7%). No other family members, including her mother, carried the mutation. She presented with exercise intolerance from age 9, and since age 20 she experienced ptosis and reduced ocular motility. A muscle biopsy revealed ragged red fibres (10%), no COX negative fibres, and many fibres with central nuclei (30%), indicating ongoing damage and repair. The present case expands the mutational and phenotypic spectrum of diseases associated with mutations in MTTK.

• 出版日期2014-2