Association of Apolipoprotein E with Neurodegenerative Diseases in North Indian Population

Abstract Background: Apolipoprotein E (ApoE) genotypes are associated with pathogenesis of various neurological diseases This study was designed to explore the association of ApoE polymorphism with risk of various neurological diseases- Alzheimer’s disease (AD), Parkinson’s disease (PD), and stroke. Methods: A cross-sectional study was performed on non-diseased and diseased subjects (AD, PD &stroke) from Institute of Human Behavior & Allied Sciences (IHBAS), New Delhi (India). 251 patients diseased and 113 non-diseased individuals were included in the study. ApoE genotyping was done in all subjects by ARMS-PCR method. Results: In AD, PD and stroke groups, 103 subjects, 36 subjects and 112 subjects were included respectively in the study, whereas control group had 113 subjects. Average age in diseased and non-diseased groups was 61.27 years (SD= 14.07) and 57.45 years (SD= 14.25) respectively. On genetic analysis for ApoE, ApoEε3/3 was found to be the most predominant genotype in both groups. Association study showed strong association of ApoEε4 allele with AD (COR: 2.73, CI: 1.32 – 5.65, p = 0. 01), whereas weak association with PD and stroke as risk factor. However, ApoEε2 emerged as a protective factor in AD, but ε2 allele had two times more risk of stroke (COR: 2.10, CI: 0.93 – 4.76, p=0.11). The presence of ApoEε3 allele was a statistically significant protective factor in both AD and PD subjects, but not significant in stroke. Conclusions: ApoEε4 allele has been found strongly associated with Alzheimer’s disease and Parkinson’s disease, whereas ApoEε2 emerged out as a risk factor for stroke and PD.