Hidden heterogeneity in Alzheimer's disease: Insights from genetic association studies and other analyses.
Despite evident success in clarifying many important features of Alzheimer's disease (AD) the efficient methods of its prevention and treatment are not yet available. The reasons are likely to be the fact that AD is a multifactorial and heterogeneous health disorder with multiple alternative pathways of disease development and progression. The availability of genetic data on individuals participated in longitudinal studies of aging health and longevity, as well as on participants of cross-sectional case-control studies allow for investigating genetic and non-genetic connections with AD and to link the results of these analyses with research findings obtained in clinical, experimental, and molecular biological studies of this health disorder. The objective of this paper is to perform GWAS of AD in several study populations and investigate possible roles of detected genetic factors in developing AD hallmarks and in other health disorders. The data collected in the Framingham Heart Study (FHS), Cardiovascular Health Study (CHS), Health and Retirement Study (HRS) and Late Onset Alzheimer's Disease Family Study (LOADFS) were used in these analyses. The logistic regression and Cox's regression were used as statistical models in GWAS. The results of analyses confirmed strong associations of genetic variants from well-known genes APOE, TOMM40, PVRL2 (NECTIN2), and APOC1 with AD. Possible roles of these genes in pathological mechanisms resulting in development of hallmarks of AD are described. Many genes whose connection with AD was detected in other studies showed nominally significant associations with this health disorder in our study. The evidence on genetic connections between AD and vulnerability to infection, as well as between AD and other health disorders, such as cancer and type 2 diabetes, were investigated. The progress in uncovering hidden heterogeneity in AD would be substantially facilitated if common mechanisms involved in development of AD, its hallmarks, and AD related chronic conditions were investigated in their mutual connection.
['Yashin|Anatoliy I|AI|', 'Fang|Fang|F|', 'Kovtun|Mikhail|M|', 'Wu|Deqing|D|', 'Duan|Matt|M|', 'Arbeev|Konstantin|K|', 'Akushevich|Igor|I|', 'Kulminski|Alexander|A|', 'Culminskaya|Irina|I|', 'Zhbannikov|Ilya|I|', 'Yashkin|Arseniy|A|', 'Stallard|Eric|E|', 'Ukraintseva|Svetlana|S|']
D000544:Alzheimer Disease D016022:Case-Control Studies D005260:Female D018740:Genetic Heterogeneity D020022:Genetic Predisposition to Disease D055106:Genome-Wide Association Study D006801:Humans D016015:Logistic Models D008137:Longitudinal Studies D008297:Male D020641:Polymorphism, Single Nucleotide
Cancer Diabetes Amyloid cascade hypothesis BBB Neurodegeneration Neuroinflammation Neuronal death Pleiotropy Response to infection Synapse loss