The lack of significant tau pathology difference at 5 m.p.i between animals injected at either 3 or 6 months of age suggests that while amyloid pathology may drive the initial spreading of tau pathology, there may be more than sufficient amyloid plaque pathology in 3-month-old animals to facilitate spreading, and spreading is instead limited by the amount of seeding material. This evidence concerns the gene MAPT and amyloidosis.