Author:
Silventoinen Karri,Piirtola Maarit,Jelenkovic Aline,Sund Reijo,Tarnoki Adam D.,Tarnoki David L.,Medda Emanuela,Nisticò Lorenza,Toccaceli Virgilia,Honda Chika,Inui Fujio,Tomizawa Rie,Watanabe Mikio,Sakai Norio,Gatz Margaret,Butler David A.,Lee Jooyeon,Lee Soo Ji,Sung Joohon,Franz Carol E.,Kremen William S.,Lyons Michael J.,Derom Catherine A.,Vlietinck Robert F.,Loos Ruth J. F.,Tynelius Per,Rasmussen Finn,Martin Nicholas G.,Medland Sarah E.,Montgomery Grant W.,Brandt Ingunn,Nilsen Thomas S.,Harris Jennifer R.,Tyler Jessica,Hopper John L.,Magnusson Patrik K. E.,Pedersen Nancy L.,Dahl Aslan Anna K.,Ordoñana Juan R.,Sánchez-Romera Juan F.,Colodro-Conde Lucia,Rebato Esther,Zhang Dongfeng,Pang Zengchang,Tan Qihua,Silberg Judy L.,Maes Hermine H.,Boomsma Dorret I.,Sørensen Thorkild I. A.,Korhonen Tellervo,Kaprio Jaakko
Abstract
AbstractWe tested the causality between education and smoking using the natural experiment of discordant twin pairs allowing to optimally control for background genetic and childhood social factors. Data from 18 cohorts including 10,527 monozygotic (MZ) and same-sex dizygotic (DZ) twin pairs discordant for education and smoking were analyzed by linear fixed effects regression models. Within twin pairs, education levels were lower among the currently smoking than among the never smoking co-twins and this education difference was larger within DZ than MZ pairs. Similarly, education levels were higher among former smoking than among currently smoking co-twins, and this difference was larger within DZ pairs. Our results support the hypothesis of a causal effect of education on both current smoking status and smoking cessation. However, the even greater intra-pair differences within DZ pairs, who share only 50% of their segregating genes, provide evidence that shared genetic factors also contribute to these associations.
Publisher
Springer Science and Business Media LLC