The influence of apolipoprotein E gene polymorphism on brain volume in healthy young adults

Abstract

Objective To explore the effect of apolipoprotein E (ApoE) gene polymorphism on brain volume in healthy young adults. Methods One hundred and ninety-three healthy young volunteers (age: 20-40 years) were recruited in Shengjing Hospital of China Medical University between August 2013 and May 2014. Two milliliters of peripheral blood were collected for the determination of ApoE genotype using direct sequencing of polymerase chain reaction (PCR) products. Brain MRI scans were performed using three-dimensional T1-weighted turbo field echo imaging sequence. The differences of brain morphometry between the e4 carriers group (e3/e4 and e4/e4 genotype) and the e4 non-carriers group (e3/e3 genotype) were analyzed using voxel based morphometry (VBM). Results The e4 carriers accounted for 14.51%(28/193) of the total population. Twenty of e4 carriers and 45 of e4 non-carriers were included in the final images analysis. VBM analysis showed that the ApoE e4 carriers had 10 atrophic brain areas compared with the e4 non-carriers (P< 0.005, uncorrected, 10 continuous voxels), which mainly located in the right anterior cingulate, the bilateral caudates, parietal lobes and lateral temporal lobes. Conclusions The influence of ApoE gene polymorphisms on brain volume has appeared in the youth. The e4 gene is related to the reductions of the gray matter volume in multiple brain areas. Key words: Apolipoproteins E; Polymorphism, genetic; Brain; Alzheimer disease