The researchers focused on Type 2 diabetes, which results from the interplay of genetic and environmental factors. To examine genetic risk factors, scientists pore over the human genome sequence. But environmental factors have been trickier to pin down, the researchers said, because there is no way to comprehensively evaluate them.
Now the Stanford scientists say they've developed an environment-wide association study -- a systematic examination of the contributions of hundreds of factors in the development of Type 2 diabetes. They said their "enviromics" approach, which mirrors genome-wide association studies, uses high-speed computers and publicly accessible databases.
In the National Institutes of Health-funded study, the researchers examined 226 separate environmental factors, such as nutrition and exposure to bacteria, viruses, allergens and toxins. They found certain factors, notably a pesticide derivative and the environmental contaminant PCB, were strongly associated with the development of diabetes. Other factors, including the nutrient beta carotene, served a protective role.
The scientists describe their work as a demonstration that computational approaches can reveal as much about environmental contributions to disease as about genetic factors. They posit the technique could be applied to other complex diseases such as obesity, hypertension and cardiovascular disorders.
The first-of-its-kind study is detailed in the online journal PLoS One.