The Determinants of Leadership : The Role of Genetic , Personality , and Cognitive Factors

A sample of 646 male twins (331 monozygotic or identical, 315 dizygotic or fraternal twins) completed a survey indicating their leadership role occupancy in work settings. Data on these individuals were also available for personality and cognitive variables. As predicted, two personality variables (Social Potency and Achievement) and a cognitive variable (a vocabulary test) were significantly correlated with the leadership variable. Subsequently, univariate and multivariate genetic analyses showed that a substantial portion of this leadership variance was accounted for by genetic factors (39 percent) while non-shared (or non-common) environmental factors accounted for the remaining variance in this leadership variable. Genetic influences were shown for the personality and cognitive factors as well. Finally, results indicated that the genetic influences for the leadership factor were substantially associated with or common with the genetic factors influencing the personality factors but not with the cognitive variable. Genetics and Leadership 2 The Determinants of Leadership: The Role of Genetics, Personality, and Cognitive Variables What are the determinants of leadership in work and organizational settings? This question has been pursued for decades. Throughout the years, a variety of constructs and predictors have been posited as determinants of leadership including general intelligence, personality, values, and even genetic factors. Though the proposition that individual differences or “traits” can predict and/or explain differences in emergent or effective leadership has sometimes been viewed with skepticism, current research has more firmly established the robustness of these types of variables in predicting leadership criteria. For example, Judge, Bono, Illies, and Gehrardt (2002) present the results of their metaanalysis showing that personality variables are consistently and reliably correlated with leadership variables, Chan and Drasgow (2001) demonstrate that a number of cognitive, personality, and motivational constructs are related to leadership across samples from different international environments, and Schneider, Paul, White, and Holcome (1999) show that a variety of constructs drawn from personality, interests, and motivation domains predicts leadership among high school students. Because of the firm foundation regarding the relationships between the constructs of individual differences and leadership, it is not far-fetched to ask whether leadership is genetically influenced. Indeed, the notion that leadership has genetic influences has been articulated in practitioner and scholarly articles over the years. For example, in a recent Harvard Business Review article, Sorcher and Brant (2002) say: “Our experience has led us to believe that much of leadership talent is hardwired in people before they reach their Genetics and Leadership 3 early or mid-twenties” (p. 81). In contrast, Kellaway (2002) reports the efforts of a major US Bank to develop all of its employees (95,000 of them) into leaders, reflecting the belief that leadership is entirely under developmental influences. It is interesting to note that almost no research exists that examines this “nature-nurture” issue using a contemporary behavior genetics research design, even though Bass (1990, p. 911) and Arvey and Bouchard (1994, p. 70) suggest that such analyses would be quite appropriate. In addition, Arvey and Bouchard (1994) indicate that while there may be evidence for genetic influences on variables like leadership, such relationships are most likely mediated through other intermediate constructs (i.e. psychological and physiological variables). The current study explores the relationships of different personality and cognitive constructs with leadership as well as the roles genetic influences play in these associations. Background: Several literature bases are important in developing the model and objectives for this study. First, the research base establishing a genetic basis for leadership is limited. To our knowledge, only one previous study has examined this issue. Johnson, Vernon, McCarthy, Molson, Harris and Jang (1998) report the results of a study using 183 MZ and 64 DZ same-sex twin pairs. The Multifactor Leadership Questionnaire (MLQ ; Bass & Avolio, 1991) and other leadership measures (e.g. adjective checklist items) were completed by these twins. Two factors resembling transactional and transformational leadership dimensions were derived from MLQ items by factor analytic procedures. Results indicated that 48% and 59% of the variance in the transactional and transformational leadership dimensions respectively was associated with genetic factors. Genetics and Leadership 4 The data also indicated that the genetic factor for the transformational dimension reflected a non-additive or dominant effect—that is, the impact of one gene depends on influence of another instead of simply “adding up”. Other analyses showed that there were common genetic factors in the covariance found between these two leadership dimensions from the MLQ and several other leadership scales. This is an important entry into the research issue of whether leadership has some genetic associations. We expand on this research in several ways. First, we incorporate alternative measures of leadership that focus on leadership role occupancy that are perhaps more clearly distinguishable from other measured facets of leadership style. Second, we incorporate an expanded model proposing and testing a model of the determinants of leadership proposing that cognitive and personality variables are related to role occupancy (see below). This is important because simply showing that a construct is heritable leaves many unanswered questions regarding how the genetic mechanisms work and through which processes. Moreover, we investigate whether and to what degree any observed relationships between personality and cognitive variables and our leadership variable are due to common genetic factors. A second literature base has to do with the research demonstrating relationships between personality dimensions and leadership. While a number of studies have demonstrated that personality variables are useful in predicting various aspects of job performance (Barrick & Mount, 1991, Hough, 1992; Lord, DeVader, & Alliger, 1986), there is also evidence that such variables predict a variety of leadership criteria. As mentioned above, Judge, Bono, Ilies, and Gerhardt (2002) meta-analyzed 222 correlations from 73 samples providing personality data according to the five-factor Genetics and Leadership 5 model (Digman, 1990) and found that measures of Extraversion correlated . 31, measures of Conscientiousness correlated . 28, measures of Openness correlated . 24, and measures of Neuroticism correlated -. 24 with leadership emergence (after corrections for unreliability but not range restriction). Similar findings have been reported previously by Hogan, Curphy, and Hogan (1994), Yukl (1998), Bass (1990), and Daft (1999). Thus, there is a substantial research base establishing a link between personality variables and leadership. In addition, the genetic basis for personality is well established dating back to Loehlin and Nichols (1976). Since then similar results have been obtained for a variety of personality measures. A few examples include the study by Jang, Livesley, and Vernon (1996) who used a twin methodology where 123 pairs of monzygotic (MZ) twins and 121 dizygotic (DZ) twins were assessed using the revised NEO Personality Inventory (Costa & McCrae, 1992). This inventory is used to capture the five factors of personality mentioned above. The estimates of genetic influence (or heritabilities) of these dimensions were as follows: Neuroticism (41%), Extraversion (53%), Openness (61%), Agreeableness (41%), and Conscientiousness (44%). Using twin pairs (about 800) drawn from the National Merit Twin Study, Loehlin, McCrae, Costa, and John (1998) showed that the “Big Five” personality factors were substantially and comparably heritable with about 50% of the variance in these personality constructs being associated with genetic factors; however little or no influence due to shared family environment was found among these twin pairs. Similar estimates were obtained by Rieman, Angleitner, and Strelau (1997) using twin samples recruited for their study in Germany. Rowe (1994) summarizes his own earlier study (Loehlin and Rowe, 1992) where multiple studies and Genetics and Leadership 6 samples were analyzed which differed in terms of their genetic relationships (e.g. twins, parent-child, adoptive siblings, etc.) as well as other sample characteristics (e.g. different age groups, different geographical areas, etc.). The heritability estimates for the big five personality dimensions ranged from . 39 to . 49, with the heritability for Extraversion demonstrating the highest estimate (.49). Rowe concluded that “Individuals who share genes are alike in personality regardless of how they are reared, whereas rearing environment induces little or no personality resemblance” (Rowe, 1994, p. 64). Moving beyond personality measures relying on the Five Factor taxonomy, Tellegen, Lykken, Bouchard, Wilcox, Segal, and Rich (1988) report a study using twins who were assessed on the 11 major personality traits as measured by the Multidimensional Personality Questionnaire (MPQ, Tellegen, 1982). Their data indicated that genetic influences were significant and substantial for all 11 scales (ranging from .39 for achievement to .58 for constraint). For excellent contemporary reviews affirming the heritabilities of personality traits see Bouchard (1997) and Bouchard and Loehlin (2001). Finally, there is a research base showing that measures of intelligence are correlated with leadership variables. For example, meta-analytic results reported by Lord, DeVader, and Alliger (1986) indicate that the mean true correlation of mea