The Petyuk group developed a RPLC-FAIMS-MS/MS technique for TDP of brain tissue from an AD patient and achieved the identification of a variety of proteoforms from synuclein, tau, and amyloid beta.157 In particular, diverse fragments of splice isoforms of tau found in this study provide insight into their proteolytic degradation pathways and their functions. Here, SNCA is linked to Alzheimer disease.