Genetic polymorphism of dopamine D2 receptors in Parkinson's disease and interactions with cigarette smoking and MAO-B intron 13 polymorphism

摘要

Genetic polymorphisms of dopamine D2 receptors (DRD2) may besusceptibility factors for Parkinson's disease due to their influence on dopamine response and association with cigarette smoking, which isinversely related to risk of Parkinson's disease. Relations of TaqIAand TaqIB DRD2 genotypes with Parkinson's disease were investigatedand tested for interactive effects with smoking and the monoamineoxidase B (MAO-B) intron 13 polymorphism previously found to be relatedto smoking. Study subjects were 152 cases of idiopathic Parkinson'sdisease and 231 controls. The smoking history of all genotyped subjectswas known. Subjects of genotype B12 were more frequent among cases thancontrols (27% and 23.8%, respectively), and were more frequent among"ever smokers" than "never smokers", among controls (27.8% and17.2%, respectively), although these associations were notstatistically significant. Neither TaqIA or TaqIB genotypes modifiedthe inverse relation of smoking and Parkinson's disease. Whengenotypes for DRD2 were considered in combination with genotypes forintron 13 of MAO-B, genotype combinations with high risk ofParkinson's disease were found; although the MAO-B/DRD2 interactiondid not reach statistical significance after Bonferroni correction formultiple comparisons, these results are suggestive of a possiblesynergism between MAOB and DRD2 genes with respect to Parkinson's disease.