• A prodromal PD and Healthy participant enrolled in PPMI Clinical protocol

• A PD participant enrolled in PPMI Clinical protocol who has not started symptomatic treatment at time of enrollment or in the first 2 years of participation.

• Able to provide informed consent

• Must have screening genetic testing documenting high binder at the at the known TSPO gene polymorphism (rs6971)

• Male or Female (Females must meet additional criteria specified below, as applicable)

• • Females must be of non-childbearing potential or using a highly effective method of birth control 14 days prior to until at least 24 hours after injection of \[18F\]DPA-714

• Non-childbearing potential is defined as a female that must be either postmenopausal (no menses for at least 12 months prior to PET scan) or surgically sterile (bilateral tubal ligation, bilateral oophorectomy or hysterectomy).

• Highly effective method of birth control is defined as practicing at least one of the following: A birth control method that results in a less than 1% per year failure rate when used consistently and correctly, such as oral contraceptives for at least 3 months prior to injection, an intrauterine device (IUD) for at least 2 months prior to injection, or barrier methods, e.g., diaphragm or combination condom and spermicide. Periodic abstinence (e.g., calendar, ovulation, symptothermal, post-ovulation methods) is not acceptable.

‣ Females of childbearing potential must not be pregnant, breastfeeding or lactating.

⁃ Includes a negative urine pregnancy test prior to injection of \[18F\]DPA-714 on day of PET scan.