Abstract
Theories on the etiology of Parkinson disease (PD) have changed since its first
description. In the famous James Parkinson monograph (1) that gave the disease its
name, Parkinson reported that “affliction to indulgence in spirituous liquors,
another to long lying on the damp ground” were among the suggested causes of the
disease. Yet by 1888, Gowers (2) reported that 15% of his patients had a family history. Indeed, today most investigators accept that PD is due to a mixture of genetic
and environmental influences interacting with each other, where the relative role of
each may change from individual to individual.