[P3-137] Genetic and clinical heterogeneity of consecutive 13 patients with central and peripheral involvement of motor neuron
Aim: To clarify clinical and genetic background of patients with central and peripheral involvement of motor neuron. Methods: Clinical studies included NCV, muscle biopsy, needle EMG, brain MRI as well as neurological examination. Genetic examination included CMT gene analyses and whole exome sequencing. Results: 13 patients whose age ranged from 11 to 44 years old were included in this study. Needle EMG showed neurological findings in all patients. Babinski reflex was positive in all patients. NCV showed normal range MCV in 11, moderate slowing in 2 and not elicitable in 1. Brain MRI showed cerebellar atrophy in 2, mild T2 high intensity in deep white matter in 1, normal in 10. Present status showed self-gait in 6, crutch gait in 3, and wheel chair in 4. Spasticity of lower extremities was leading symptom in 6 (Group 1), who were initially diagnosed as cerebral palsy or spastic paraplegia. Genetic analysis revealed heterozygous mutation in KIF1A in 2 and homozygous mutation in TFG in 1. On the other hand, 7 patients (Group 2) initially presented as neuropathy because of deformed foot, later appeared spastic paresis. Genetic analysis revealed heterozygous mutation of MFN2 in one, BSCL2 in 2 and compound heterozygous mutation of HEXB in 1. Presently, causative gene mutations were found in almost half of patients. In this next generation sequencing era, careful clinical examination is getting more important for precise genetic diagnosis.