Genome screen for loci influencing age at onset and rate of decline in late onset Alzheimer's disease.

We performed an affected sib-pair (ASP) linkage analysis to test for the effects of age at onset (AAO), rate of decline (ROD), and Apolipoprotein E (APOE) genotype on linkage to late-onset Alzheimer's disease (AD) in a sample comprising 428 sib-pairs. We observed linkage of mean AAO to chromosome 21 in the whole sample (max LOD = 2.57).

Full genome screen for Alzheimer disease: stage II analysis.

We performed a two-stage genome screen to search for novel risk factors for late-onset Alzheimer disease (AD). The first stage involved genotyping 292 affected sibling pairs using 237 markers spaced at approximately 20 cM intervals throughout the genome. In the second stage, we genotyped 451 affected sibling pairs (ASPs) with an additional 91 markers, in the 16 regions where the multipoint LOD score was greater than 1 in stage I.