Overview

• Direct inheritance of obesity-related genes from both parents explains most variation in children’s BMI but mothers exert an additional influence beyond DNA transmission.
• Genetic nurture from maternal alleles not passed to offspring alters the prenatal and early developmental environment, amplifying obesity risk.
• Fathers’ genetic impact on offspring BMI is confined to alleles inherited by the child, with minimal indirect environmental effects.
• The analysis applied phenotypic linear regression and Mendelian randomization to data from 2,621 UK mother–father–child trios published in PLOS Genetics.
• Lead author Dr Liam Wright suggests that reducing maternal BMI during pregnancy could mitigate intergenerational transmission of obesity.