C9orf72 and multiple system atrophy: This review briefly presents the genes that are likely linked with MSA (SNCA, COQ2, MAPT, GBA1, LRRK2, and C9orf72) and those associated with PSP (MAPT, LRRK2, DCTN1, NPC1, PARK2, TARDBP, GRNTBK1, and C9orf72) highlighting the overlapping genetic pathways of MSA and PSP and suggesting future research directions.