Family Background and Adolescent Weight: An Examination of Social and Genetic Influences

Molly A. Martin, Columbia University
Gary Sandefur, University of Wisconsin at Madison

This project seeks to better analyze the family-level social factors associated with adolescent weight after accounting for genetic influences. We model adolescents' body-mass index (BMI) using sibling resemblance models and the genetic sample of the National Longitudinal Study of Adolescent Health. By conducting sibling model analyses in a structural equation framework, we account for unmeasured family background characteristics and determine what proportion of the variation in adolescent weight is due to variation between families and variation within families. We estimate separate sibling models for each sibling-pair type (i.e., monozygotic twins, dizygotic twins, full siblings, half siblings) and test for differences in the influence of various family background factors across sibling-pair types.