A way to predict whether a child will become obese through genetic testing has emerged. The World Obesity Federation predicts that by 2035, half of humanity will be obese or overweight. It is expected that early management of children identified as at risk for obesity can prevent various diseases caused by obesity.
Researchers from the University of Copenhagen in Denmark and the University of Bristol in the UK announced on the 21st in the international journal Nature Medicine that they have developed a polygenic risk score for measuring obesity risk using genetic data.
Genetic variations are one of the causes of obesity. For example, there are genetic variations in the brain that are involved in appetite. The polygenic risk score serves as a comprehensive indicator that calculates these variations. The researchers developed the polygenic risk score based on genetic information from over 5 million individuals.
The genetic information was provided by the Genetic Investigation of Anthropometric Traits (GIANT) consortium and the genetic testing company 23andMe. According to the researchers, there was a correlation between the polygenic risk score and body mass index (BMI) from age 5 until adulthood.
The researchers validated the obesity measurement index they developed. During this process, they utilized various information, including the BMI of 500,000 people. The information referenced data from the UK 'Children of the 90s' study, which tracks the growth and development of children born in the UK in the 1990s. As a result, the polygenic risk score had double the accuracy in predicting obesity compared to existing indicators. The researchers stated that if it is possible to predict whether an individual will become obese when they become an adult through genetic testing, early intervention will also be feasible.
Obesity is associated with diabetes and hypertension. While treatments for obesity include exercise, medication, and surgery, none are 100% effective. Professor Joo-joon from the Gwangju Institute of Science and Technology (GIST) noted, 'If it is known in advance whether someone will be an obese adult, it may be possible to manage proactively accordingly.'
However, the researchers stated, 'While the polygenic risk score shows excellent predictive accuracy for those of European ancestry, its accuracy decreases somewhat for those of African ancestry,' adding that 'additional studies including diverse populations are necessary.'
References
Nature Medicine (2025), DOI : https://doi.org/10.1038/s41591-025-03827-z