Epidemiology, environmental risk factors and genetics of Parkinson's disease.

Parkinson's disease (PD) is a frequent neurodegenerative disease with a premotor phase that lasts several years. Risk factors that have been linked to PD are tobacco, caffeine, black tea, pesticides and calcium channel blockers. Some risk factors may be due to inverse causality (e.g. changes in personality during the premotor phase). The genetics of PD are complex with a contribution of Mendelian (e.g. SNCA, LRRK2, Parkin, Pink1,…) and non-Mendelian factors (e.g. single nucleotide polymorphisms). Glucocerebrosidase gene mutations (Gaucher disease) are currently the strongest genetic risk factor for PD. Studying risk factors will help to better understand the pathogenesis of PD.