More recently, researchers have detected the rs75932628single-nucleotide polymorphism (SNP) within the triggering receptor expressed onmyeloid cells 2 (TREM2) gene, leading to an R47Hsubstitution, which increases the risk of developing AD in carriers by virtually thesame magnitude as the presence of one APOE ε4allele [59]; reviewed by [60]. Here, APOE is linked to Alzheimer disease.