Table 1 Talking points to share with patients with late-onset Parkinson’s disease (PD).

• Most PD is caused by multiple factors, both genetic and environmental, many of which are not yet known.

• Advancing age increases the chance of developing disease.

• Genes that you inherit, from your parents, usually play a role in developing PD.

• Some families have major gene variants, dominantly inherited, that significantly increase the risk for developing PD.

• Current genetic testing can look for some of these major gene variants to aid in risk assessment, risk counseling, and providing a reason for development of the disease.

• However, not all PD genes or changes in known genes can be identified with today’s technology. Therefore, a negative/normal genetic test result does not rule out all genetic factors including the possibility of recurrence in relatives.

• Whether a major gene variant is present or not, environment, age, and other factors can also influence chances of developing disease.