Further evidence is emerging for a possible role of the adaptive immune in the development of Parkinson's disease as toll‐like receptor 4 (TLR4) gene polymorphisms have been linked to sporadic Parkinson's disease (Zhao et al., 2015) and α‐synuclein can induce the up‐regulation of TLRs (Beraud et al., 2011). The gene discussed is TLR4; the disease is Parkinson disease.