The Heritability of Hope: Exploring Genetics and the Environment as Sources of Variation
Abstract
Hope is an important character strength and contributor to well-being. Although theory and empirical work have focused on individual variation, few studies have contributed a behavioural genetics perspective. The current study used twin modelling to explore genetic, common, and unique environmental contributions to Snyder’s cognitive trait hope. Data from the TwinsUK registry included 917 same-sex twin pairs [637 monozygotic (76 men, 561 women) and 280 dizygotic (15 men, 265 women)]. Modelling results were presented for composite scores, pathway and agency subscales, age- and sex-adjusted composites, and a women-only sample. The best-fitting model estimated heritability at 41 - 43% (36 - 38% in the subscales) with the remaining variance attributed to the unique environment. The findings underscore the substantial role of genetics and individualized experiences in predicting trait variation and provide a foundation for research to build upon Hope Theory and better understand the development and maintenance of this important trait.