[The pathogenesis of Parkinson's disease: a hint from insights of familial Parkinson's disease].

Parkinson's disease (PD) is a progressive movement disorder characterized by resting tremor, rigidity, akinesia, and postural instability. In addition, PD is characterized by the appearance of Lewy bodies in the remaining neurons. The exact etiology for this disease is still unknown. However, genetic-environmental interaction could contribute the pathomechanisms of PD. Indeed, totally seven causative genes responsible for familial PD have been identified. Since discovery of familial PD (FPD), genetic PD models have been developed. Thus, we think that the research field of FPD provides us a good hint for the pathogenesis of nigral degeneration in not only familial but also sporadic form of PD.