Purpose: The manifestation of Parkinson’s disease (PD) is characterized by bradykinesia, resting tremor,
and rigidity. The etiology of PD remains unknown. Recently several studies suggest that some environmental
and genetic factors may be related to the cause of PD. Genetic variation in xenobiotic metabolizing
enzymes involved in the disposition of pesticides, such as paraoxonase I (PON 1), may increase
the risk of PD. We investigated the association between PON1 polymorphism, pesticides exposure and
risk of Parkinson’s disease in Taiwanese population.
Methods: We enrolled 162 controls and 125 patients with idiopathic PD. Histories of exposures to environmental
factors and other information were collected with a questionnaire filled out during a face-toface
interview with the subject. The data included years of farming, drinking water sources, occupational
exposures to pesticides, duration and the initial age of the pesticides exposure. Buccal mucosa
cells are collected from each subject and PON1 polymorphism at codon 54 (L and M alleles) is studied
with PCR-based restriction fragment length polymorphism (RFLP) analysis.
Results: There is significant association between the risk of PD and exposure to pesticides (OR=1.72, 95%
CI=1.07-2.75). On the otherhand, no significant differences are found in PON1 genotype or allelic distribution
between PD and control groups. We further investigated participants who had reported exposure
to pesticides and found that the frequency distribution of PON1 genotypes did not differ significantly
between patients and controls.
Conclusion: The present survey reveals the close relationship between exposure to pesticides and
Parkinson’s disease. There are no significant differences in the distribution of PON1 genotypes
between cases and controls.
