APOE E2 Carriers Showed Worse Associative Learning Than E3 Carriers in a Cognitively Normal Aging Han Chinese Population

Abstract Background: Polymorphism in the APOE gene has been shown to be associated with cognitive function, however, the related studies are not consistent. To investigate the relationship between APOE gene polymorphism and cognitive function, we conducted the current cross-sectional study specifically to investigate the effect of different APOE genotypes on cognitive performance in normal elderly adultsMethods: A total of 156 older adults with normal cognitive function were enrolled in the current study. According to different genetic types, they were divided into three groups: 1) E2/2 or E2/3 (APOE E2); 2) E3/3 (APOE E3); and 3) E2/4, E3/4, or E4/4 (APOE E4). Then Montreal Cognitive Assessment (MoCA) and Neuropsychological Test Battery (NTB) were used to assess their global cognitive function and domain-specific cognitive function, respectively. Results: The results of Kruskai-Wallis H test showed that the scores of associative learning in APOE E2 group were lower than that in E3 groups (p<0.05), but there was no statistical difference (p>0.05) in associative learning between E2 group and E4 group, and E3group and E4 group. Similarly, there was no difference (p>0.05) in the global cognitive function among the three groups.Conclusion: APOE E2 is associated with decreased associative learning function than APOE E3 in a cognitively normal aging Han Chinese population.