Common variants of the apolipoprotein E (APOE) gene have a major impact on the risk of developing Alzheimer's disease (AD). Relative to homozygotes with the common E3 allele, the APOE4 variant (C112R) Show more
Common variants of the apolipoprotein E (APOE) gene have a major impact on the risk of developing Alzheimer's disease (AD). Relative to homozygotes with the common E3 allele, the APOE4 variant (C112R) increases risk by 3.5-fold in E3/E4 heterozygotes and 15-fold in E4 homozygotes. Since the E3 and E4 alleles differ only by a single nucleotide, gene editing of E4 to E3 is a potential strategy to reduce AD risk in E4 homozygotes. Because the APOE pool in the brain is separate from systemic APOE, editing to treat AD would ideally be directed to the brain. Following Show less