Effect of CLU and PICALM polymorphisms on AD risk: A study from south India.

OBJECTIVES: To study the association of apolipoprotein E (APOE), Clusterin (CLU) and phosphatidylinositol binding clathrin assembly protein (PICALM) polymorphisms in Alzheimer's disease (AD) subjects compared to cognitively normal control subjects in an Indian population. METHODS: The study subjects included persons with AD (N=243) and age group matched healthy controls (N=164). All the AD subjects were evaluated using a standard protocol. DNA was isolated from whole blood. APOE (rs7412, rs429358), CLU (rs11136000) and PICALM (rs3851179) were genotyped. General linear model was used to test the association between the individual risk genotypes and AD. RESULTS: The presence of APOE ε4 was associated with AD after adjusting for age and gender (p<0.0001). There was no association observed with AD at both rs11136000 CLU (p=0.25) and rs3851179 PICALM (p=0.54). CONCLUSION: Our results confirmed a significant association of APOE ε4 carrier status with AD. No association was observed for CLU and PICALM with AD. This might be due to a different genetic background. There are no previous reports of these polymorphisms in an Indian cohort. Future Indian AD studies should investigate additional SNPs in a larger sample size in these genes.

Dementia and diabetes mellitus: association with apolipoprotein e4 polymorphism from a hospital in southern India.

Objective. To evaluate the association of Apolipoprotein E4 (ApoE4) in Alzheimer's dementia (AD) with comorbid diabetes mellitus (DM). Methods. The study included subjects with Alzheimer's dementia (AD) (n = 209), individuals with non-Alzheimer's dementia (nAD) (n = 122), individuals with parental history of AD (f/hAD) (n = 70), and control individuals who had normal cognitive functions and no parental history of dementia (NC) (n = 193). Dementia was diagnosed using International Classification of Diseases-10 revision (ICD-10) criteria. DM was assessed on the basis of self-report and/or use of antidiabetic medications. ApoE genotyping was done using sequence-specific primer polymerase chain reaction. Results. ApoE4 allele frequencies were highest among AD with comorbid DM (0.35) followed by AD without DM (0.25), nAD with DM (0.13), nAD without comorbid DM (0.12), and NC (0.08). Frequency of ApoE4 in persons with f/hAD was 0.13. The association of AD with co-morbid DM in ApoE4 carriers was more in comparison to NC with DM (OR = 5.68, P = 0.04). Conclusion. There is a significant association between AD with co-morbid DM and ApoE4 genotype.