Parkinson's Disease: Genetics, Environment and Prevention

The underlying causes of Parkinson’s disease (PD) are not yet completely understood, but researchers think it is caused by a combination of genetics and environmental factors for most people.
Circadian rhythm dysregulation is linked to many of the non-motor symptoms in Parkinson's disease. These issues often occur years before motor-related symptoms (tremors, gait issues) occur. The CRY and PER genes control what is known as the ‘negative arm’ of the clock, and their levels rise at night. The BMAL1 and CLOCK genes make up the positive arm of the circadian clock, and they are maximized during the day. Genetic variants to PER1 have been linked to increased Parkinson's risk. [PMC4623766]
Organophosphate exposure is also linked to Parkinson’s risk. Chlorpyrifos and other organophosphates increase the risk of Parkinson’s disease, depending on the amount of exposure and the genetic variants the person carries. The BCHE gene encodes butylcholine esterase. Two copies of the K-variant is associated with a 30% decrease in BChE and an increased risk of Parkinson's. [PMC6224461]