Q. Sample 17) Alzheimer’s disease vs control: brain donors: Subjects were 1086 brain donors of mean age 82 who were 43% male and at least 65 years of age at death. Brains and clinical data met pathological criteria for Alzheimer’s disease or control status. DNAs were subjected to Affymetrix 500k genotyping. From the files TGEN_WGA_ DATA_ recode_ped.txt [4], genotype calls for 552 control and 859 AD individuals allowed us to calculate χ2 values for the AD vs control differences for each SNP, select SNPs which displayed χ2 values with p < 0.05 as nominally-positive and assess which of these nominally-positive SNPs fell into chromosomal clusters such that at least 3 nominally-positive SNPs that represent both array types lie ≤ 25 kb from each other.
