Below are both my father’s and uncle’s pathology results from their brain autopsies. Both my dad and I registered to become brain donors very early on when we first started participating in research, and my dad and uncle’s legacies live on through their gifts to science. Brain pathology is highly variable in people who carry LRRK2 variants and who died with parkinsonism. This is a very intriguing mystery. Some people just show degeneration in the substantia nigra with no other evidence of pathology. Many LRRK2 brains show tau pathology (what is commonly seen in Alzheimer’s), and about half show classic alpha-synuclein pathology. My dad showed very severe alpha-synuclein pathology, as well as tau and beta-amyloid pathology. And, he had some limited TDP-43 (what is commonly seen in ALS) pathology confined to the amygdala region of his brain. There seems to be a lot of overlap in pathology among neurodegenerative diseases. In contrast, despite also carrying the LRRK2 G2019S variant, my dad’s brother showed zero Lewy bodies. Columbia University plans to test all of their LRRK2 brains for a-syn oligomers using a new special assay since some recent papers suggest that LRRK2-PD brains might show evidence of a different form of a-syn that is not visible using traditional methods. I hope more answers will come to light as the field progresses.