The first genome-wide association study (GWAS, “jē’ wŏs”) of age-related macular degeneration appeared in 2005 (Klein et al., 2005). Since then, nearly 400GWAS studies have been published in the NHGRI GWAS catalog (http://www.genome.gov/26525384, accessed 20 September 2009). The GWAS approach has been exceptionally successful in identifying common genetic variants that predispose to a variety of complex human diseases and biochemical and anthropometric traits and was named the “breakthrough” of 2007 by the journal Science. Indeed, the GWAS method has performed beyond expectations.
