Furthermore, the application of sargramostim (GM-CSF) for Parkinson’s disease (PD) treatment has been linked to the gene and/or protein expression levels of potential biomarkers such as LRRK2, HMOX1, TLR2, TLR8, RELA, ATG7, and GABARAPL2, which may predict therapeutic responses to immunomodulatory therapies [148]. The gene discussed is HMOX1; the disease is Parkinson disease.