TREM2 and multiple system atrophy: Selected interleukins (IL-1A, IL-1B, IL-8) and TNF-α genetic polymorphism increased the risk of MSA, as well as variants of Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) and nucleotide-binding oligomerisation domain containing 2 (NOD2) (25–29).