Dopamine beta-hydroxylase activity in cerebrospinal fluid of idiopathic torsion dystonia. Since a postmortem biochemical study and a genetic linkage study of idiopathic torsion dystonia suggested possible involvement of dopamine beta-hydroxylase (DBH), we determined CSF DBH activities of Jewish and non-Jewish patients with childhood-onset idiopathic torsion dystonia and found no differences from a control population. 