By 2005, the genetic community was ready to embark on several GWAS. The first published GWAS reported the discovery of a functional SNP in the complement factor H that was associated with age related macular degeneration [21]. The study used a small case control design comparing the allele distribution of ~100,000 SNPs in 96 cases and 50 controls. The small sample size was balanced by a very careful ascertainment of cases and controls, gender matching, and stringent quality control rules to reduce the chance for spurious associations. The initial analysis identified one SNP in strong allelic association with the disease and resequencing of the region identified a novel functional variant. This first successful example of a GWAS was soon followed by several other applications to a variety of common diseases including prostate and breast cancers [22–27], Crohn’s disease [28–30], coronary artery disease and diabetes [6,31,32], fetal hemoglobin expression [33], and other traits [34]. Table II provides examples of GWAS relating to hematological disease. The catalogue curated by Terri Manolio at the NHGRI provides updated information about results of GWAS [44],
