Although variations in several genes have been identified that contribute to the disease, these rare genetic defects account for a small proportion of the overall prevalence of the disorder. “Previous studies have shown that individuals with Parkinson’s disease are over twice as likely to report being exposed to pesticides as unaffected individuals” says the study’s lead author, Dana Hancock, “but few studies have looked at this association in people from the same family or have assessed associations between specific classes of pesticides and Parkinson’s disease.”
The study of related individuals who share environmental and genetic backgrounds that might contribute to Parkinson’s disease enables researchers to identify specific differences in exposures between individuals with and without the disease. The research team from Duke University Medical Center and the University of Miami recruited 319 patients and over 200 relatives. They used telephone interviews to obtain histories of pesticide exposure, living or working on a farm, and well-water drinking.
The authors detected an association between pesticide use and Parkinson’s disease. Among these, the strongest were between the disorder and use of herbicides and insecticides, such as organochlorides and organophosphates. No association was found between Parkinson’s disease and well-water drinking or living or working on a farm, which are two commonly used proxies for pesticide exposures. Future genetic studies of Parkinson’s disease should consider the influence of pesticides, since exposure to pesticides may provide a trigger for the disease in genetically predisposed individuals.
MEDICA.de; Source: BioMed Central