Research on microglia has shown that TLR2 or TLR4 stimulation can increase the expression and phosphorylation of LRRK2.259,260 The researchers identified microglia-specific chromatin regions that regulated LRRK2 expression and showed that a specific regulatory DNA element containing the PD-associated genetic variant rs6581593 modulates LRRK2 expression in microglia. Here, LRRK2 is linked to Parkinson disease.