The lentiviral approach used in the present study could similarly be used to examine the effects of aging on the toxicity of mutant proteins involved in other neurodegenerative diseases (e.g. PS1/APP for Alzheimer's disease, and DJ-1, PINK-1, and LRRK2 for Parkinson's disease). Here, LRRK2 is linked to early-onset autosomal dominant Alzheimer disease.