Moreover, to explore whether E. coli is a specific environmental factor to interact with LRRK2 risk variants to trigger PD-like pathological alterations, Lrrk2RP/+ mice were orally gavaged with K. pneumoniae, Proteus mirabilis (P. mirabilis), and dextran sodium sulfate (DSS) (SupplementaryFigure S3a)31,32. This evidence concerns the gene LRRK2 and Parkinson disease.