For many decades various environmental variables have been interpreted as causal factors without adequate genetically informative designs being used. In the last decade or so, many large genetically informative studies began to be published showing that the statistical relationships between environmental variables and outcome variables were not causal, but resulted from a genetic confound i.e. environment variables are often heritable too. This page is meant as a collection of such studies, so that one may adjust one’s expectations. In short, one should stop making the sociologist’s fallacy.
Each header is the alleged environmental cause, each bullet is the supposed outcome.
Note: some studies also found shared environmental confounds, so while genetics did not explain all of the association, the purported environmental cause didn’t either.
Childhood family income
Maternal smoking during pregnancy
- Cognitive (low academic achievement and general cognitive ability) and externalizing outcomes (criminal conviction, violent criminal conviction and drug misuse), but effects found for pregnancy outcomes (birth weight, preterm birth and being born small for gestational age)
Being a teenage mother
- Young adult criminal convictions: shared environmental and genetic confound, 67% and 31% respectively
Early age at first sexual intercourse
- Psychosocial maladjustment: Cannabis use, alcohol abuse/dependency, depressive symptoms, criminal offending, adolescent childbearing, various amounts of genetic and shared environmental confounding
Low socioeconomic status (education, income)
High school friendships