Table 1.

Unique features of the EGDS adoption design.

EGDS adoption design features	Behavior genetic terminology	Monograph terminology
EGDS children are raised by parents who are not biological relatives, and therefore the adopted children do not share segregating genes with their rearing parents	Passive gene-environment correlation	Effects of genes common to parents and children
In an adoption study, correlations between birth parent characteristics and adoptive parent/family characteristics reflect the impact of the child’s genetic or prenatally acquired characteristics, operating directly on the adoptive family environment	Evocative gene-environment correlation	Child effects on parenting
Birth parent characteristics may increase some children’s likelihood of a favorable or maladaptive outcome as a function of their rearing environment; in addition, some rearing environments may be beneficial to children, depending on their genetic characteristics.	Gene by environment interaction	Child effects moderate the influences of parenting on children’s own development
In an adoption study, the prenatal environment is contributed by the birth mother, and is thus intertwined with genetic influences, rather than post-natal rearing environmental influences. Careful measurement of the prenatal environment can increase inferences about genetic influences	N/A	Prenatal environment
EGDS birth parents are assessed multiple times, from a few months post-partum to a decade or more later. This reduces measurement error in indices of genetic influences	N/A	N/A