People's genes tend to have a greater influence on their risk of developing disease than their environment, though it can vary, CNN reports.
Researchers from the US and Australia turned to a health insurance database to assess how genes and the environment contribute to 560 disease-linked phenotypes in more than 56,000 twin pairs born in or after 1985 in the US. The researchers followed their health over time and used their ZIP codes and other data to link them to certain environmental factors, such as socioeconomic status, air pollution, and average monthly temperature.
As the researchers led by Harvard Medical School's Chirag Patel report in Nature Genetics this week, they found that about 40 percent of the diseases they examined had a genetic component and 25 percent had an environmental one. As CNN notes, some diseases were influenced more by genes than by the environment and vice versa. For instance, Axios notes that the environment had the greatest effect on eye and respiratory disorders, and the least effect on reproductive and cognitive conditions.
"You get people who are very deterministic, who say 'it's genes' or 'it's environment.' This shows it's a mixture," Jeffrey Craig from Deakin University School of Medicine, who was not involved in the new study, tells CNN.