POLYMORPHISMS OF DOPAMINE-RECEPTOR AND TRANSPORTER GENES AND PARKINSONS-DISEASE

Disturbances of the dopamine system are involved in the pathogenesis o f idiopathic Parkinson's disease (PD). Although genetic factors may pl ay a role in the etiology of PD, there is little direct evidence impli cating a specific gene. We conducted a study to test the hypothesis th at allelic variations of the dopamine receptors (D2, D3, D4) and the d opamine transporter (DAT) contribute to the susceptibility to PD. Asso ciation analyses of 70 Japanese PD patients and the same number of age -matched controls did not reveal any association between alleles of th e D2, D3 or D4 receptor genes or the DAT gene and PD. Thus, our result s suggest that factor(s) other than allelic variations of these key pr oteins in the dopamine system contribute to the susceptibility to PD.