New tool can identify children who are likely to become obese in adulthood
Academics used detail on genetic variations from more than five million people to create a tool called a polygenic risk score, which analyses people's genetics to work out their risk of developing obesity. File picture
A tool which can measure a child's risk of becoming obese in later life has been created by scientists.
It is hoped the new resource will one day mean those at highest risk will get targeted support to prevent them from becoming obese in the first place.
The tool, which assesses a person's genetic risk of obesity, works twice as well as any other obesity risk predictor, academics said.
As well as identifying children at risk of obesity, it can also predict how well obese adults will respond to targeted weight-loss programmes.
Academics used detail on genetic variations from more than five million people to create a tool called a polygenic risk score, which analyses people's genetics to work out their risk of developing obesity.
The tool could explain 17.6% of variation in body mass index score (BMI) from people, they found.
Researchers, led by academics at the universities of Copenhagen and Bristol, tested whether the risk score was associated with obesity using datasets of the physical and genetic characteristics of more than 500,000 people.
They found it could successfully predict weight-gain during childhood — from the age of just two and a half — through to adolescence.
"Overall, these data show that polygenic scores have the potential to improve obesity prediction, particularly when implemented early in life," the authors wrote in the journal .
Lead author of the research, assistant professor Roelof Smit from the University of Copenhagen, said: "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.
"Intervening at this point could theoretically make a huge impact."
He said BMI was not a good predictor for a child's obesity risk in later life, but the genetic predictor could offer insight into the risk from early years.
"Essentially it's fixed at conception already very early in life, you're able to essentially quantify what someone's innate predisposition is for BMI," he said.
"So, being able to say something about someone's innate biology for obesity risk."
Meanwhile, the research team also looked at people taking part in "intensive lifestyle intervention" programmes.
People with a higher risk score lost more weight, but were also more likely to regain it.
Prof Smit added: "There is a huge amount of variation in how people respond to these interventions.
"What we observed was the higher someone's score was, the more they tended to respond to the intervention — people who had a higher score tended to lose more weight in the first year.
"And we also saw that people who had the higher scores tended to gain more weight."
