By Robert Preidt
WEDNESDAY, July 27, 2016 (HealthDay News) -- Shared lifestyles and surroundings may play as strong a role as genes in diseases that run in families, a new study indicates.
The study included medical histories of more than 500,000 people and their families in the United Kingdom. The information included blood and adoptive relatives. The researchers focused on 12 common diseases, including high blood pressure and heart disease, as well as several cancers and neurological diseases.
Factors shared by family members can have a significant influence on a person's risk for some diseases. These factors include the same living space and similar eating habits.
The impact of genes on disease risk may be overestimated by 47 percent when shared family factors aren't taken into account, the study authors contended.
The study offers "precise estimates of the role of genetics in these important diseases. It also identified those diseases where the shared family environment is important, such as heart disease, hypertension and depression," Chris Haley, a professor in the MRC Human Genetics Unit at the University of Edinburgh, said in a university news release.
The results help clarify the value of genetic testing for disease risk and highlight the need to pinpoint environmental factors that increase disease risk, the researchers said.
Findings from the study were published recently in the journal Nature Genetics.