The genetic architecture of body mass index from infancy to adulthood modified by parental education

Objective: A higher prevalence of obesity in lower socioeconomic classes is common in Western societies. This study examined the role of gene–environment interactions in the association between parental education and body mass index (BMI) from infancy to the onset of adulthood. Methods: Parentally reported BMI from 1 to 13 and self-reported BMI from 14 to 20 years of age were collected in 16,646 complete Dutch twin pairs and analyzed by genetic twin modeling. Results: At 7 to 8 years of age, children whose parents had middle or low educational levels had more excess weight than the children of more highly educated parents, and the difference increased until 18 to 20 years of age. The major part of the BMI variation was explained by additive genetic factors (