Lipoprotein Lipase HindIII Intronic Polymorphism in a Subset of Iranian Patients with Late-Onset Alzheimer’s Disease

Objective: Lipid metabolism is involved in the pathogenesis of late-onset Alzheimer’s disease (LOAD). Lipoprotein lipase (LPL) is a multifunctional enzyme that plays a major role in lipid metabolism; its abnormal function seems to be related, either directly or indirectly, to the pathogenesis of many diseases such as atherosclerosis, coronary artery disease (CAD) and Alzheimer’s disease (AD) . HindIII polymorphism is a common LPL genetic variant shown to increase the risk of LOAD. The present research investigates whether this polymorphism is involved in the pathogenesis of Iranian LOAD patients. Materials and Methods: In this case control study ,allele and genotype frequencies for the HindIII polymorphism of the LPL gene in 100 patients affected with LOAD and 100 healthy controls were determined by reaction-restriction fragment length polymorphism (PCR-RFLP) and compared using the chi-square and Fisher’s exact tests. Results: LPL H+H+ genotype frequency in LOAD patients was 58%, which was significantly higher than controls (44%). There was a 1.75-fold increased risk for the development of LOAD in carriers of the H+H+ genotype compared to non-carriers (OR=1.75; 95%CI: 1.00-3.07; p=0.048). When adjusted for sex, the H+H+ genotype was more frequent in patients than controls; this difference was more remarkable in males (OR: 1.90; 95% CI: 1.08-3.34; p=0.024). The mean age of disease onset did not differ in patients with the LPL H+H+ genotype compared to unaffected individuals. Conclusion: This study confirms the association between the H+H+ genotype with LOAD and supports the correlation of this genotype of the LPL gene with risk of developing LOAD in Iranian patients with AD.