Heritability × SES Interaction for IQ: Is it Present in US Adoption Studies?

ABSTRACT: An interaction between socioeconomic status (SES) and the heritability of IQ, such that the heritability of IQ increases with higher SES, has been reported in some US twin studies, although not in others, and has generally been absent in studies outside the US (England, Europe, Australia). Is such an interaction present in US adoption studies? Data from two such studies, the Texas and the Colorado Adoption Projects, were examined, involving 238-469 adopted children given IQ tests at various ages. A mini multi-level analysis was made of the prediction of the IQs by the SES of the rearing home (a composite of parental education and occupation), by the birth mother's intelligence, and by the interaction of the two. Neither study showed any substantial heritability × SES interaction: the effec

SUBMITTER: Loehlin JC 

PROVIDER: S-EPMC9255665 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature