APOE and LRPAP1 gene polymorphism and risk of Parkinson's disease

Epidemiologic findings suggest that lipids and alteration in lipid metabolizing protein/gene may contribute to the development of neurodegenerative disorders. The aim of the current study was to determine the serum lipid levels and genetic variation in two lipid metabolizing genes, low-density lipoprotein receptor-related protein-associated protein (LRPAP1) and apolipoprotein E (APOE) gene in Parkinson's disease (PD). Based on well-defined inclusion and exclusion criteria, this study included 70 patients with PD and 100 age-matched controls. LRPAP1 and APOE gene polymorphism were analyzed by polymerase chain reaction and restriction fragment length polymorphism, respectively. Fasting serum lipid levels were determined using an autoanalyser. The logistic regression analysis showed that high levels of serum cholesterol [odds ratio (OR) = 1.101, 95 % confidence interval (CI95%) = 1.067-1.135], LRPAP1 I allelic variant alone (OR = 2.766, CI95% = 1.137-6.752) and in combination with APOE epsilon 4 allelic variant (OR = 4.187, CI95% = 1.621-10.82) were significantly associated with increase in PD risk. Apart from that, the high levels of LDL cholesterol appears to have a protective role (OR = 0.931, CI95% = 0.897-0.966) against PD. The LRPAP1 I allelic variant may be considered a candidate gene for PD, predominantly in patients having the APOE epsilon 4 allelic variant.