Abstract: Methods and compositions for determining whether a subject will age without developing cognitive decline are provided. An exemplary method includes detecting one or more allelic variants in a gene encoding low density lipoprotein-related protein 1B. In a preferred embodiment, the detecting step is accomplished by contacting a sample obtained from the subject with a probe that forms a detectable complex with a nucleic acid in the sample containing an allelic variant indicative of aging without developing cognitive decline, wherein detection of the allelic variant in the sample indicates that the subject will age without developing cognitive decline.

Abstract: Methods and compositions for determining whether a subject will age without developing cognitive decline are provided. An exemplary method includes detecting one or more allelic variants in a gene encoding low density lipoprotein-related protein 1B. In a preferred embodiment, the detecting step is accomplished by contacting a sample obtained from the subject with a probe that forms a detectable complex with a nucleic acid in the sample containing an allelic variant indicative of aging without developing cognitive decline, wherein detection of the allelic variant in the sample indicates that the subject will age without developing cognitive decline.

Abstract: Methods and compositions for determining whether a subject will age without developing cognitive decline are provided. An exemplary method includes detecting one or more allelic variants in a gene encoding low density lipoprotein-related protein 1B. In a preferred embodiment, the detecting step is accomplished by contacting a sample obtained from the subject with a probe that forms a detectable complex with a nucleic acid in the sample containing an allelic variant indicative of aging without developing cognitive decline, wherein detection of the allelic variant in the sample indicates that the subject will age without developing cognitive decline.

Abstract: The presence of a restriction site in the gene for apolipoprotein CI (APOCI) is a risk factor for Alzheimer's disease. The invention involves determining the presence of the restriction site in biological samples from patients suspected to be at risk for Alzheimer's disease. The presence of the restriction site indicates that the patient may be at higher risk for the disease; those who are heterozygotes may be at intermediate risk; while those lacking the site are at a lesser risk for the disease. PCR amplification and the use of improved oligonucleotide primers specific to the region surrounding the restriction site as well as digestion with the restriction enzyme may be used to determine the presence of the site. APOCI provides a genetic marker for Alzheimer's disease that is distinct from APOE4. The methods disclosed provide a more accurate and definitive screening technique for the early identification of Alzheimer's disease compared to screening of APOE4 alone in some populations.