APOE and early-onset autosomal dominant Alzheimer disease: However, recent findings from clinical trials with n-3 PUFA supplementation showed efficacy on depressive symptoms in non–Vapolipoprotein E (APOE) ε4 carriers, and on cognitive symptoms only in very mild Alzheimer's disease (AD) subgroups, MCI patients, and cognitively unimpaired non-APOE ε4 carriers.