Genetic predisposition to Parkinson's disease: CYP2D6 and HFE in the Faroe Islands.

OBJECTIVE To investigate whether the genetic variants of CYP2D6 and HFE are more frequent in Parkinson's disease (PD) patients compared with controls in a population where the prevalence of these variants and PD are increased. METHODS Blood samples were collected from 79 PD patients and 154 controls in the Faroe Islands. Genotyping for the 'CYP2D6*3, *4, *6 and *9' alleles and for the C282Y and H63D mutations were performed by real-time polymerase chain reaction before Taqman assessment. RESULTS The frequency of CYP2D6 poor metabolizers among the patients was not higher compared with the frequency found in the control group (chi2 test, P=0.86). The odds ratio was 0.92 (95% confidence interval: 0.44-1.90). Neither was a difference in HFE genotype or allele frequencies found between the patients and the controls, and the C282Y and H63D mutation carrier frequencies did not reveal any difference (chi2 test, P=0.50 and 0.60, respectively). CONCLUSION This study does not support an association between PD and mutations of the CYP2D6 and HFE genes, although a weak association cannot be excluded. The high frequency of PD in the Faroes is most likely the result of interactions between multiple genetic and environmental factors, still to be identified.