Figure 1. Genomewide- association studies of pharmacogenomics traits
The number of pharmacogenomics(PGx) genome-wide association studies (GWAS) is limited, and such studies have focused on populations of European ancestry. The US National Human Genome Research Institute and European Bioinformatics Institute (NHGRI-EBI) GWAS Catalog, which was formed in 2008, was used to obtain information about the number, ethnicity and types of studies performed to date. (a) Total number of GWAS of three main human characteristics: diseases, traits and drug responses (pharmacogenomics). (b) Number of studies accumulated each year for each type of GWAS. (c) Number of PGx studies conducted in various ethnic populations. Few PGx GWAS have involved non-European populations, with only two reported in individuals of Hispanic ancestry and two in individuals of African ancestry. (d) The major categories of PGx GWAS. A total of 216PGx GWAS were annotated in the GWAS Catalog. The four major PGx GWAS focus on drugs used in the treatment of cancer, neuropsychiatric disease, cardiovascular disease and asthma. Among the 216PGx GWAS, 145 and 69 studies focus on drug responses and toxicities or adverse drug events, respectively. However, only two of the studies focus on drug levels. There are fewer PGx GWAS of adverse drug reactions (ADRs) compared with drug efficacy (69 versus 145); many of the PGx GWAS of ADRs are limited to hypersensitivity reactions. A full list of the PGx studies annotated in the GWAS Catalog is available in Supplementary information S1 (table). With a total of only 216PGx GWAS listed in the GWAS Catalog, these observations reveal major gaps in PGx GWAS. There is a need for PGx GWAS across the range of pharmacological agents and in non-European populations.