Background: Type 2 diabetes mellitus (T2DM) is associated with chronic hyperglycemia and lipid metabolism. A previous genome-wide association study revealed the TOMM40-APOE region as novel locus for T2DM susceptibility.
Objective: This association study was conducted to determine the genetic effects of APOE single nucleotide polymorphisms (SNPs) on T2DM susceptibility and lipid profiles in a Korean population.
Methods: A total of 6 tagging SNPs, including rs7412 and rs429358, were selected for ε genotype analysis and genotyped in 1436 subjects, consisting of 352 T2DM patients and 1084 unaffected controls.
Results: Logistic regression analyses were conducted and there were no significant associations among the APOE 6 tagging SNPs, ε genotypes, and haplotypes with T2DM susceptibility. To investigate the association of the APOE tagging SNPs with the lipid profiles, a regression analysis was conducted. As a result, rs7412 was significantly associated with the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels (Pcorr = 2.30 × 10-5 and 3.39 × 10-13, respectively) in the unaffected controls. The ε2 allele and ε3 allele were significantly associated with the TC (Pcorr = 4.46 × 10-6 and 0.02, respectively) and LDL levels (Pcorr = 3.54 × 10-14 and 0.0006, respectively) in the unaffected controls. Further analysis of only the unaffected controls was conducted. As a result, the APOE alleles ε2 and ε3 showed a significant association with the TC and LDL levels (P < 0.05).
Conclusion: The results of this study may help in understanding APOE polymorphisms and ε alleles and lipid profiles, which have been highly linked to T2DM, in a Korean population.
Keywords: Apolipoprotein E (APOE); Korean population; Lipid profiles; Single nucleotide polymorphism (SNP); T2DM (type 2 diabetes mellitus).