Chunk #57 — Online Methods — Genome-wide survival association study datasets — (4) Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE)
using the Illumina Infinium II HumanHap550chip v3·0 ® array in 2007–2008 according to the manufacturer’s protocols. Genotyping was attempted in persons with high-quality extracted DNA (n=6,449). From these 6,449, samples with low call rate (<97.5%, n=209), with excess autosomal heterozygosity (>0.336, n=21), with sex-mismatch (n=36), or if there were outliers identified by the IBS clustering analysis (>3 standard deviations from population mean, n=102 or IBS probabilities >97%, n=129) were excluded from the study population with some persons meeting more than one exclusion criterion; in total, 5,974 samples were available with good quality genotyping data, 42 persons were excluded since they did not undergo cognitive screening at baseline, hence their cognitive status was uncertain. An additional 61 persons were excluded because they suffered from dementia other than AD at baseline. After exclusion of prevalent dementia, a sample of 5752 persons was available. The Rotterdam Study (including its brain magnetic resonance imaging (MRI) and neurological components) has been approved by the institutional review board (Medical Ethics Committee) of the Erasmus Medical Center and the Netherlands Ministry of Health, Welfare and Sports Participants were screenedfor prevalent dementia in 1990–93 using a three-stage process; those free of dementia remained under surveillance for incident dementia,
