In conclusion, a higher number of autopsies has led to the observation of a broader spectrum of anti-IgLON5 disease-associated neuropathologies that can be currently stratified in a continuum of progressive brainstem neurodegeneration and tau accumulation that ranges from stage 1, an early “minimal/non-tau brainstem degeneration”, to stage 3, the extensive anti-IgLON5 disease-related “brainstem-predominant 3R + 4R tauopathy”, with some variations, and with or without other concomitant protein aggregates, particularly TDP-43. This evidence concerns the gene MAPT and tauopathy.