Beyond AD, the A30P model of PD crossed with the ApoE−/− background was found to attenuate alpha-synuclein-based neurodegenerative phenotypes, increasing the level of soluble alpha-synuclein protein, significantly delaying the onset of motor symptoms and improving overall median survival of these mice as compared to A30P/ApoE wildtype mice [418]. The gene discussed is APOE; the disease is Alzheimer disease.