Similarly, some patients with hereditary L-DOPA-responsive dystonia, a neurological disorder with clinical similarities to PD, have mutations in the TH gene and decreased TH activity and/or stability.
Endogenous neopterin measurement in unstimulated lymphoblasts is an accurate tool to identify dysfunctional GCH1 and a potential specific diagnostic marker for dysfunctional GCH1 in DRD and other neurologic disorders.
Dopa-responsive dystonia (DRD) is an autosomal-dominant neurological disorder which appears to result from a genetically determined deficiency of striatal dopamine.