A new genetic analysis led by researchers at the Universities of Copenhagen and Bristol has unveiled a new polygenic risk score (PGS) that predicts the future risk of obesity from childhood. This innovation holds potential for early targeted interventions, significantly impacting public health.
In a new study published in the journal Nature Medicine, an international consortium of researchers, led by the Universities of Copenhagen and Bristol, has introduced a novel genetic analysis that may revolutionize the approach to combating obesity. This research, harnessing data from over 5 million individuals, has culminated in the development of a polygenic risk score (PGS) that can predict the propensity for obesity from an early age.
Examining genetic data from the largest and most diverse dataset ever, including contributions from the Genetic Investigation of Anthropometric Traits (GIANT) consortium and consumer DNA testing firm 23andMe, the researchers meticulously crafted a PGS associated with adult obesity.
This score is not only the most accurate to date but is twice as effective as previous methods at predicting who is likely to become obese.
“What makes the score so powerful is the consistency of associations between the genetic score and body mass index before the age of five and through to adulthood — timing that starts well before other risk factors start to shape their weight later in childhood,” lead author Roelof Smit, an assistant professor at the University of Copenhagen, said in a news release. “Intervening at this point could theoretically make a huge impact.”
The World Obesity Federation anticipates that over half of the global population will be overweight or obese by 2035. Current interventions like lifestyle changes, surgery and medications are not universally accessible or effective.
This new genetic analysis offers a promising alternative by identifying children and adolescents at high genetic risk for obesity early on, allowing for preventative strategies tailored to individuals at a young age.
“Obesity is a major public health issue, with many factors contributing to its development, including genetics, environment, lifestyle and behavior. These factors likely vary across a person’s life, and we believe that some of these originate in childhood,” added second author Kaitlin Wade, an associate professor in epidemiology at the University of Bristol. “We were delighted to contribute data from the Children of the 90s study to this exceptional and insightful research. We hope this work will contribute to detecting individuals at high risk of developing obesity at an earlier age, which could have a vast clinical and public health impact in the future.”
The effectiveness of this PGS lies in its ability to account for subtle genetic variations influencing factors such as brain functions and appetite, which together determine a person’s body mass index. The score explained almost a fifth of the variation in BMI among individuals — a substantial improvement over previous studies.
Beyond genetics, the researchers also explored how lifestyle interventions like diet and exercise interact with genetic obesity risk. It was observed that individuals with a higher genetic risk can respond more effectively to these interventions, though they also tend to regain weight more rapidly once the intervention concludes.
Despite its promise, the PGS has limitations. It was found to be more accurate in predicting obesity among those of European ancestry compared to those of African ancestry, highlighting the need for future research that encompasses more representative population groups.
Source: University of Bristol