Apolipoprotein-E gene polymorphism and lipid profiles in Alzheimer's disease

In this study, the relationship between lipid profiles of sera and apolipoprotein E (apo E) gene polymorphism was investigated in 35 patients with Alzheimer's disease (AD) and 29 healthy people. Apo E genotypes and allele frequencies of the AD patient group were: apo E2/3, 2 (5.7 percent); apo E2/4, 1 (2.9 percent); apo E3/3, 26 (74.3 percent); apo E3/4, 5 (14.3 percent); apo E4/4, 1 (2.9 percent); epsilon 2, 3(4.2 percent); epsilon 3, 59 (84.2 percent); epsilon 4, 8 (11.4 percent). The healthy group's apo E genotypes and allele frequencies were: apo E2/3, 1 (3.4 percent); apo E3/3, 27 (93.1 percent); apo E3/4, 1 (3.4 percent); epsilon 2, 1 (1.7 percent); epsilon 3, 56 (96.5 percent); epsilon 4, 1 (1.7 percent). In Alzheimer's cases, epsilon 4 allele frequencies increased significantly as compared to the healthy group (p < 0.05). When the effects of the apo E isoforms on lipid profiles were evaluated, a relationship between apo E epsilon 4 allele and high total levels of serum cholesterol was found, whereas of apo E epsilon 2 allele was associated with the low total cholesterol of serum, although the difference was not statistically significant (p > 0.05). This study confirms the association of apo E epsilon 4 allele with lipid profiles in AD patients.