Zellers’ Research Looks at Cannabis Use By Twins

Last month,  Dr. Stephanie Zellers’ (PIB, ‘22) article titled “Impacts of Recreational Cannabis Legalization on Cannabis Use: A Longitudinal Discordant Twin Study” was published in the scientific journal, Addiction.  Zellers is now a postdoctoral researcher at the University of Helsinki, Finland. Co-authors include Jacob E. Anderson Dr. Gretchen R.B. Saunders (PIB ‘19), and Drs. William Iacono, Matt K. McGue, and Scott Vrieze in the Department of Psychology.

The study examined the effects of recreational adult cannabis use in twins. The participants included 111 twin pairs who were separated, living in different states with different policies related to recreational cannabis use. Zellers’ research shows that the twin who lived in a state where recreational marijuana was legal used marijuana 20% more frequently than their co-twin who lived in a state where it was not legal. This result suggests that increased cannabis use can be attributed to its legalization. Additionally, Zellers’ work highlights that cannabis legalization may decrease the heritability of cannabis use. 

Stephanie Zellers, PhD, post-doc research fellow in the Department of Psychology at the University of Minnesota.