For further investigation in the subsequent analyses, we selected seven key SNPs in seven AD-associated genes with evidence of association, including CASS4 rs911159 (P = 2.2 × 10−5), EPHA1 rs10952552 (P = 0.0018), FERMT2 rs4901317 (P = 0.0041), MEF2C rs9293506 (P = 0.0081), PLD3 rs11672825 (P = 0.0071), RIN3 rs1885747 (P = 0.0097), and SLC24A4 rs67063100 (P = 0.0038). This evidence concerns the gene MEF2C and Alzheimer disease.