Furthermore, injection of Gal‐9‐Aβ fibrils into the hippocampus of APP/PS1 mice triggered more severe Aβ deposition, synaptic dysfunction, and cognitive impairment than injection of pure Aβ fibrils, indicating that Gal‐9‐seeded Aβ may represent a novel Aβ strain. The gene discussed is APP; the disease is Cognitive impairment.