%0 Case Reports %T Parkinsonism in spinocerebellar ataxia with axonal neuropathy caused by adult-onset COA7 variants: a case report. %A Ouchi S %A Ishii K %A Kosaki K %A Suzuki H %A Yamada M %A Takenouchi T %A Tamaoka A %J BMC Neurol %V 23 %N 1 %D 2023 Jun 1 %M 37264311 %F 2.903 %R 10.1186/s12883-023-03202-w %X BACKGROUND: Individuals with variants of cytochrome c oxidase assembly factor 7 (COA7), a mitochondrial functional-related gene, exhibit symptoms of spinocerebellar ataxia with axonal neuropathy before the age of 20. However, COA7 variants with parkinsonism or adult-onset type cases have not been described.
METHODS: We report the case of a patient who developed cerebellar symptoms and slowly progressive sensory and motor neuropathy in the extremities, similar to Charcot-Marie-Tooth disease, at age 30, followed by parkinsonism at age 58. Exome analysis revealed COA7 missense mutation in homozygotes (NM_023077.2:c.17A > G, NP_075565.2: p.Asp6Gly). Dopamine transporter single-photon emission computed tomography using a 123I-Ioflupane revealed clear hypo-accumulation in the bilateral striatum. However, 123I-metaiodobenzylguanidine myocardial scintigraphy showed normal sympathetic nerve function. Levodopa administration improved parkinsonism in this patient.
CONCLUSIONS: COA7 gene variants may have caused parkinsonism in this case because mitochondrial function-related genes, such as parkin and PINK1, are known causative genes in some familial Parkinson's diseases.