First Korean Case of C9orf72 -Related Amyotrophic Lateral Sclerosis With Progressive Supranuclear Palsy-Like Features

Palsy-Like Features Dear Editor,Chromosome 9 open reading frame 72 (C9orf72) hexanucleotide repeat expansion (HRE) is the most common genetic cause of amyotrophic lateral sclerosis (ALS) in Western populations, but it has not been reported in Korean patients with ALS.1,2 We report the first Korean ALS case accompanied by parkinsonism, caused by a C9orf72 HRE.A 73-year-old woman of Korean descent presented with a one-year history of progressive gait disturbance, followed 3-4 months later by dysarthria and dysphagia.One year after symptom onset, she became wheelchair-bound.Her medical history included rheumatoid arthritis and hypothyroidism for over 30 years.She had no family history of ALS, frontotemporal dementia (FTD), parkinsonism, or psychiatric disorders.On initial examination, severe hypokinetic dysarthria, slow and stiff gait with short, shuffling steps, and bilateral postural hand tremor were observed; modest weakness of the extensor muscles was noted only in the lower limbs, with all other muscles graded 5 on the Medical Research Council (MRC) scale.The Berg Balance Scale score was 10, indicating marked postural instability (scores