The Equal Environments Assumption in the Post-Genomic Age: Using Misclassified Twins to Estimate Bias in Heritability Models

29 Pages Posted: 24 Jan 2011 Last revised: 28 Jan 2011

See all articles by Dalton Conley

Dalton Conley

New York University (NYU) - Department of Sociology; National Bureau of Economic Research (NBER)

Emily Rauscher

affiliation not provided to SSRN

Date Written: January 2011

Abstract

While it has long been known that genetic-environmental covariance is likely to be non-trivial and confound estimates of narrow-sense (additive) heritability for social and behavioral outcomes, there has not been an effective way to address this concern. Indeed, in a classic paper, Goldberger (1979) shows that by varying assumptions of the GE-covariance, a researcher can drive the estimated heritability of an outcome, such as IQ, down to zero or up close to one. Survey questions that attempt to measure directly the extent to which more genetically similar kin (such as monozygotic twins) also share more similar environmental conditions than, say, dizygotic twins, represent poor attempts to gauge a very complex underlying phenomenon of GE-covariance. Methods that rely on concordance between interviewer classification and self-report offer similar concerns about validity. In the present study, we take advantage of a natural experiment to address this issue from another angle: Misclassification of twin zygosity in a nationally-representative study (Add Health). Since such twins were reared under one "environmental regime of similarity" while genetically belonging to another group, this reverses the typical GE-covariance and allows us bounded estimates of heritability for a range of outcomes of interest to medical and behavioral scientists.

Suggested Citation

Conley, Dalton and Rauscher, Emily, The Equal Environments Assumption in the Post-Genomic Age: Using Misclassified Twins to Estimate Bias in Heritability Models (January 2011). NBER Working Paper No. w16711, Available at SSRN: https://ssrn.com/abstract=1744666

Dalton Conley (Contact Author)

New York University (NYU) - Department of Sociology ( email )

New York, NY 10012
United States

National Bureau of Economic Research (NBER)

1050 Massachusetts Avenue
Cambridge, MA 02138
United States

Emily Rauscher

affiliation not provided to SSRN

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
16
Abstract Views
358
PlumX Metrics