Besides, some gut-inflammation risk genes could also increase the risk of MSA, such as LRRK2 and NOD2; therefore, putative proinflammatory bacterial genera may participate in stimulating MSA process (Franke et al., 2010; Heckman et al., 2014; Engen et al., 2017; Cao et al., 2018; Villumsen et al., 2019). This evidence concerns the gene NOD2 and multiple system atrophy.