Abstract:

Objective To investigate the changes in episodic memory encoding（EME）and retrieval per⁃ formance（RP），and correlation of these changes withApoE，MTHFR gene C677T polymorphism in the patients with Mild Cognition Impairment（MCI）. Methods 227 subjects were enrolled in this study，including 109 patients with MCI（MCI group）and 118 patients with normal control group（NC group）. Employing EME and RP test，The scores of EME，RP and reaction time were inspected in all the subjects. Applying restriction fragment length polymorphism detected，the ApoE，MTHFR gene C677T polymorphism were detected，and its feature of its associ⁃ ation with the scores of episodic memory were analyzed. Results （1）The accuracy rate of encoding，retrieval accuracy in MCI group were lower than that in NC group，the differences were statistically significant（P < 0.05）. The reaction time of encoding and retrieval in MCI were obviously extended compared with that in NC group，the results were significantly different（P < 0.05）.（2）The difference in distribution frequency of ApoEε3/ε4、ε4/ε4、 MTHFR gene C677T TT genotype in MCI group were higher than that of NC group，the results were different （P＜0.05）.（3）The differences in score of EME and RP in different ApoE，MTHFR C677T genotypes among the two groups were statistically significant（P < 0.05）. Conclusions （1）The ability of encoding and retrieval of episodic memory in the elderly MCI patients of Han nationality in Guangzhou were decreased.（2）Polymorphism of ApoE gene and MTHFR gene were important risk factors of MCI in the elderly of Han nationality in Guangzhou， the gene polymorphism has an effect on encoding and retrieval of episodic memory in MCI patients.

Key words: