Heritability of Personality

The aim of this study is to simplify the issue of the concept of heritability, to give an introduction to the behavioral genetic theory and methods, as well as to give an overview of the current knowledge about heritability of personality and the quantitative and molecular genetic approach to estimate heritability. Following that, results on heritability of personality are summarized. In addition, we reanalyzed all available behavioral genetic studies published before 2010, which were included in Vukasović and Bratko (2015) meta-analysis, to estimate the correlations between different family members: 1) monozygotic twins reared together; 2) monozygotic twins reared apart; 3) dizygotic twins reared together; 4) dizygotic twins reared apart; 5) mother and offspring; 6) father and offspring. Estimates of the family resemblance for personality were .54 from intraclass correlations for twin pairs reared together, .45 for intraclass correlations for monozygotic twin pairs reared apart, and .26 and .28 for familial aggregation. This finding is in line with the conclusion of the previous meta-analysis, which showed that the study design is a significant moderator of personality heritability, with twin studies showing higher estimates compared to family and adoption studies. Following that, findings from molecular genetic studies on personality and from gene-environment interaction studies are summarized. Finally, recommendations for future studies are given.