The inverse variance weighted (IVW) analysis indicated that Myeloid DCs (p = 0.004), HVEM expression on CD45RA− CD4+ T cells (p = 0.007), CD62L− CD86+ Myeloid DCs (p = 0.015), and HLA DR expression on monocytes (p = 0.019) were associated with a reduced risk of PD. The gene discussed is CD4; the disease is Parkinson disease.