Polymorphisms in the apolipoprotein E (APOE) gene in gerontopsychiatric patients

Two recently described polymorphisms in the promoter region of the apolipop rotein E (APOE), the -491A/T and Th1/E47csT/G polymorphism, have been sugge sted to be associated with an increased risk for Alzheimer's disease (AD) i ndependent from the APOE epsilon4 carrier status. We studied the associatio n between the APOE epsilon4 polymorphism and the -491A/T and Th1E47csT/G po lymorphisms in a sample of 118 healthy, non-demented controls and 239 conse cutively recruited gerontopsychiatric patients diagnosed as: Alzheimer's di sease (N = 89), age mild cognitive impairment (N = 32), memory complainers without any cognitive deficit (N = 54) and depression/other psychiatric dis orders (N = 64),to test whether the investigated polymorphisms have a high enough selectivity and specificity to distinguish between the different ger ontopsychiatric disorders or to differentiate AD genetically from other for ms of dementia, respectively. Also a possible association with the APOE eps ilon4 polymorphism was examined. We found a statistically significant assoc iation between the APOE epsilon4 allele and Alzheimer's disease (p = 0.0001 ) and age associated memory impairment (p = 0.006). Our study failed to sho w an association between the promoter polymorphisms -491A/T and Th1E47csT/G in the APOE gene and gerontopsychiatric disorders either alone or in relat ionship to the APOE epsilon4 polymorphism. However, if we combine our resul ts with three previous published positive reports there seems to be an asso ciation between the -491A/T polymorphism and AD, though its size is less th an found in the original publication.