Extensive research exists on the topic of genetic makeup and its influence on personality. For example, a study conducted in 2004 found that such character traits as agreeableness and conscientiousness showed a complex genetic architecture, whereas the common pathway model could be used for the explanation of neuroticism and extraversion (Lewis & Bates, 2014). However, neither the independent pathway model nor the common pathway model could be used for a detailed explanation of different personality traits and features.
Thus, a new research model (based on the previous ones) was created to explain the relationship between genes and character traits. It should be noted that the common pathway model “constrains common covariance to the indicators to be explained by a single latent factor”, whereas this latent factor is influenced by genetic and environmental factors (Lewis & Bates, 2014, p. 12). According to the authors, neuroticism, extraversion, and openness, as well as agreeableness and conscientiousness, could be explained by “a model with a single common genetic factor” (Lewis & Bates, 2014, p. 13). However, another set of traits, honesty-humility, could also be explained by a single common genetic factor, which was not anticipated.
Another study researched the role of SLC6A4, BDNF, and GABRA6 genes in traits related to anxiety. An association between TT genotype and anxiety-related traits, namely, Anticipatory Worry, was detected. However, it is important to note that previous researchers did not show it. What is more, the Neuroticism dimension, also tested in the study, provided negative results (i.e. no clear relation to a particular genotype or genes). Therefore, one can assume that not all personality traits are entirely tied to genes, although some of them have remarkably stronger connections to genotypes or genes than others do.
The authors also mentioned other genes that could be linked to anxiety-related traits: for example, the Val66Met polymorphism (BDNF gene) was associated with anxiety-related traits by other researchers as well (Arias et al., 2012). Another interesting observation is that gene-gene interaction could also be responsible for different character traits. The interaction between the 5-HTTLPR polymorphism (5-HTT gene) and Val66Met polymorphism (BDNF gene) in individuals with the Met/Met genotype led to much higher scores for HA (Harm Avoidance) (Arias et al., 2012). The researchers also pointed out that their study did not support the assumption of other researchers that the 5-HTTLPR polymorphism of the SLC6A4 gene and HA or Neuroticism could be related.
As can be seen, the relationship between genes and personality traits is possible, even though some inconsistency exists due to the complexity of such research. Furthermore, one should also remember that the moderate heritability of such complex connections between genes and traits is also possible, which allows researchers to study and evaluate families to provide any clarity on the influence of genes on one’s personality.
However, as it was already mentioned by Arias et al. (2012), gene-gene interactions often remain underinvestigated, which results in inconsistency in the findings of various studies. Not only genes and genetic makeup itself but also different gene interactions, environmental, social, psychological, ecological, and other backgrounds can affect one’s personality traits. It would also be intriguing to find out how and why personality changes are possible and whether genes are not the primary influence on people’s personalities. A possible or proven association between intelligence and genetic makeup can significantly influence our understanding of character traits related to creativity, genius, and ability to learn and adapt quickly.
References
Arias, B., Aguilera, M., Moya, J., Sáiz, P. A., Villa, H., Ibáñez, M. I., & Fananas, L. (2012). The role of genetic variability in the SLC6A4, BDNF and GABRA6 genes in anxiety‐related traits. Acta Psychiatrica Scandinavica, 125(3), 194-202.
Lewis, G. J., & Bates, T. C. (2014). How genes influence personality: Evidence from multi-facet twin analyses of the HEXACO dimensions. Journal of Research in Personality, 51(2), 9-17.