Genetic epidemiology with a capital E, ten years after.

More than a decade after Duncan Thomas gave his presidential address at the International Society for Genetic Epidemiology entitled "Genetic Epidemiology with a Capital E," genetic epidemiology has gone mainstream. Epidemiology has taken its place not only in gene discovery studies but also in characterizing genetic effects and gene-environment interactions in populations. Furthermore, epidemiologic principles are being applied to the evaluation of genetic tests. We used an online informatics tool, the HuGE Navigator, to describe the growth in the field in the past decade. We developed the HuGE Navigator as a means to continuously monitor the evolving information obtained from epidemiologic studies of the human genome. Between 2001 and 2010, the HuGE Navigator included 57,005 articles published in 2,396 journals. During that period, the annual number of publications increased almost four-fold. The articles included 986 genome-wide association studies and 1,879 meta-analyses of gene-disease associations. The total number of authors of published studies grew from 12,907 in 2001 to 48,389 in 2010. The number of diseases also increased over time, from 697 medical subject headings in 2001 to 1,404 in 2010. Gene-environment interaction was mentioned explicitly in 17% of published abstracts, almost half of which focused on gene-drug interactions. Clearly, genetic epidemiology has gone "capital E" in the past decade; however, the ever-expanding volume and variety of genomic information poses a formidable challenge for developing appropriate methods for analysis, synthesis, and inference on complex genetic and environmental effects. We extend Duncan Thomas' capital E to include "Evaluation" as the tools of epidemiology are increasingly used to assess how genome-based information can be applied in medicine and public health.