A novel MYH7 Leu1453pro mutation resulting in Laing distal myopathy in an Irish family

作者：Lefter Stela^*; Hardiman Orla; McLaughlin Russell L; Murphy Sinead M; Farrell Michael; Ryan Aisling M

来源：Neuromuscular Disorders, 2015, 25(2): 155-160.

DOI：10.1016/j.nmd.2014.09.007

• MYH7
• Laing distal myopathy
• Epilepsy
• Brain white matter disease

Authors describe clinical, pathological, imaging and genetic findings in the first Irish family with Laing distal myopathy in whom a novel mutation in the human slow beta-myosin heavy chain (MYH7) gene has been identified. A kindred of 14 over 6 generations included 6 individuals with childhood onset distal lower limb weakness in a scapula-peroneal distribution with subsequent proximal upper and lower limb weakness. Finger extensor weakness especially in the 3rd-5th fingers was present in each and two patients had "hanging big toe" sign. Three patients were non-ambulatory by middle-age. One patient developed cardiomyopathy and two patients had respiratory muscle impairment. Intriguingly, brain white matter lesions and epilepsy were present in three patients. Muscle biopsy revealed fibre-size variation, rimmed vacuoles, mild-extensive central nucleation, redundant and folded sarcolemmal membrane and Z band streaming. Genetic analysis revealed a novel heterozygous mutation in the MYH7 gene in one patient which co-segregated perfectly in the remaining 5 affected members and was absent in six unaffected members.

• 出版日期2015-2