A third study [100] using AD-discordant siblings found 865 hypomethylated and 716 hypermethylated sites, as defined by a DiffScore of 20 or greater (log transformation of P value, corresponding to 0.05 < p < 0.01 according to Illumina materials), with GABRP among the top thirty hypermethylated sites. This evidence concerns the gene GABRP and Alzheimer disease.