The typical clinical presentation of dopa‐responsive dystonia, which is also called Segawa disease, is a young age of onset, with predominance in females, diurnal fluctuation of lower limb dystonia, and fair response to low‐dose levodopa. This disease has both autosomal dominant and autosomal recessive inheritance. Autosomal dominant Segawa disease is caused by GCH1 mutation on chromosome 14q22.1‐q22.2. Here, we report the case of a male patient with genetically confirmed Segawa disease and atypical presentations including no diurnal symptom fluctuation and insufficient response to levodopa. The patient's father who had the same mutation presented parkinsonism in old age. We also review the literature to address the broad clinical heterogeneity of Segawa disease and the influence of onset age on clinical presentation.

This study indicates that the EIF4G1 mutation is rare in Taiwan, which is consistent with other reports from Asia. Ethnicity could have a great influence on EIF4G1 in PD. Further large scale studies are warranted to evaluate the association of PD and EIF4G1 gene.