The contribution of heredity in the manifestation of the benevolent relation to other people is around 45 percent. It researchers found, after analyzing the ability to warmly relate to people and to perceive this attitude of the 464 pairs of twins — both monozygotic and dz. In a study published in the journal Communication Monographs, also refers to a different contribution of genetics in relation to gender and age.
The theory of exchange of affection, which examines how, why, and why people enter into romantic relationships, suggests that such communication is an adaptive behavior that promotes survival and reproduction: for example, close relationships contribute to protect people from the harmful effects of stress. According to the main postulate of this theory, the need and ability to warm relations are innate, and evolved in human form because of attachment of parents to the newborn child. From this point of view of interpersonal differences in emotional communication can be observed in populations partly because of genetic variation, although, of course, they may be impacted by external factors (environmental factors).
To assess the impact of the relationship of genetic factors and environmental factors on the development of abilities friendly attitude to people and to perceive this attitude from others, Cory Floyd (Floyd, Kory) with colleagues from the University of Arizona used the twin method. In total, the study involved 229 pairs of monozygotic twins and 235 pairs of dz twins.
Assessment of the ability to warmly relate to other people was conducted using a questionnaire of the TAS-G: it had to indicate the degree of agreement with ten statements on a scale from one (completely disagree) to nine (completely agree). Assessment of the ability to perceive the warm attitude from other people was conducted using a questionnaire of the TAS-R, consisting of six claims with the same method of response.
In the primary analysis revealed that women scored significantly more points in the questionnaire TAS-G than men (p < 0.001). The same pattern was observed in a situation with a questionnaire of the TAS-R (p < 0.001). Vnutrivenno correlation for both abilities have shown that monozygotic twins were more similar to each than dz twins. It is noteworthy that vnutrivenno correlation was much stronger for identical twins than for dz twins female. Also, it was found that the correlation of responses was influenced by the age of the test: revealed significant differences in the responses of young twins and twins over the age of 50. Such differences in correlations show that genetic influence varies between gender and age subgroups.
The results of a system analysis point to the contribution of genotype in both abilities. In this model, the contribution of heredity in the ability of warm relations with people amounted to 45 percent, and 55 percent were related to individual factors, while the contribution of environmental factors was equal to zero (p < 0.001). The ability of perception of such a relationship the contributions are divided differently: the contributions of heredity was equal to 21%, while environmental factors explained 14 percent of the differences, and the individual factors of 65% (p < 0.001).
It was also found that genetic factors largely implemented in women. The influence of genetic factors in the ability of heat to treat other people, they have accounted for 48 percent, and the ability to take from others — 42 percent. In men, the influence of genetics was zero. Among twins older than 50 years, scientists found a decrease of the contribution of genetics to both sign, and 39 percent for the benevolent relation to other people and 37 per cent for the perception of such an attitude. Among respondents under the age of 50 years the genetic factor for the ability to be good to others amounted to 40 percent, and only 2 percent for the perception of warm relationships.
Conclusion, attributing the 45 percent inheritance friendly people, does not mean that 45 percent of the love affair of a particular individual has a genetic basis: it refers to the variation in all (or at least studied, population). In addition, one or the other share the inheritance of the trait does not mean that this percentage is predetermined and is beyond human ability to control it. Finally, we cannot exclude the possibility of an explanation of each factor determining warm feelings for another person, interactions gene-environment, where each genetic factor is implemented only under certain environmental conditions.
On the topic of romantic relationships held more than one job. For example, the eight-year study showedthat people do not change their behavior in the relationship when you change the partner.