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Updated: Jun 13, 2026

Rating L-DOPA-Induced Dyskinesias in the Unilaterally 6-OHDA-Lesioned Rat Model of Parkinson's Disease
Published on: October 4, 2021
Marked improvement in Segawa syndrome after L-dopa and selegiline treatment
Elif Yosunkaya1, Ender Karaca, Sarenur Basaran
1Department of Medical Genetics, Cerrahpasa Medical School, Istanbul University, Istanbul, Turkey. yosunkayafenerci@hotmail.com
Abstract:
Three brothers, born to parents who were first cousins, were referred for progressive diffuse dystonia. Initial physical examinations revealed minor dysmorphic features, e.g., bifrontal narrowing, downslanting palpebral fissures, low-set ears, upturned nostrils, and microretrognathia, as well as neurodevelopmental delay. Absence of eye contact and head control, diffuse dystonia, hypokinesia, choreoathetosis, tremor, increased deep tendon reflexes, diffuse muscle atrophy, and spasticity were evident during neurologic evaluations. After laboratory investigations, imaging studies, and the exclusion of other causes of childhood dystonia, the children were diagnosed with Segawa syndrome. A molecular analysis of the tyrosine hydroxylase gene revealed a novel P492R (1475 C>G) mutation, further confirming the clinical diagnosis. After 1-month therapy with 2 mg/kg/day l-dopa, no changes in signs were evident. Selegiline was added, which greatly improved the clinical picture. Segawa syndrome in three brothers resulted from a novel mutation in the tyrosine hydroxylase gene. Treatment with a combination of l-dopa and selegiline led to favorable outcomes.
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