Scientists have developed multi-ancestry polygenic risk scores (PRS) that predict an individual’s likelihood of developing adult obesity based on genetic variants present early in life. An international study utilizing over five million genetic samples demonstrated that these PRS explain up to 18% of BMI variance in Europeans and varying percentages in other ancestry groups. The findings, published in Nature Medicine, suggest the PRS could identify children at high genetic risk for obesity before age five, enabling earlier targeted lifestyle interventions. The study also observed different responses to interventions and weight regain correlated to genetic risk levels.