Dr. William W. Dressler (University of Alabama), Dr. Mauro C. Balieiro (Paulista University), and Dr. José Ernesto dos Santos (University of São Paulo) will undertake research on how genotype and culture interact to affect individual psychological well-being, as assessed by depressed mood. A variety of genes are thought to influence mood states, but these genes do not simply determine mood. Rather, these genes appear to interact with and modify experience in the social environment. Culture, in the form of shared models of everyday life, defines the nature of experience in the social environment. Cultural consonance is the degree to which individuals approximate, in their own beliefs and behaviors, the prototypes for belief and behavior encoded in cultural models. Higher cultural consonance in a number of different cultural domains is associated with more positive mood. This research will examine how the effect of cultural consonance on depressed mood changes in the presence of different genetic polymorphisms for two genes in the serotonin system (the serotonin transmitter gene and the 2A receptor gene). It is hypothesized that specific variants of these genes act as amplifiers of experience; when an individual has one or both of these variants, the effect of cultural consonance will be larger.
The research will be conducted in Ribeirão Preto, Brazil, a city of 500,000 people in the north of the state of São Paulo. Using a mixed-methods research design, cultural model in various domains (lifestyles, social support, family life) will be investigated and measures of cultural consonance will be derived from these analyses. In a survey of 600 persons selected from a stratified random sample of the community, data on cultural consonance, depressive symptoms, and genotype will be collected (along with sociodemographic variables and alternative explanatory variables). Data analysis will determine if the effect of cultural consonance is modified by genotype.
This research will help to answer very important questions about the relative influences of genes and culture in determining individual well-being. It will contribute significantly to a further biocultural synthesis and to promoting international research collaboration.
The primary aim of this project was to replicate and extend research on gene-environment interactions and subjective well-being among persons of diverse socioeconomic backgrounds in an urban center in Brazil. Research in the past decade has shown that individuals with different genetic profiles are variably influenced by stressful environmental events and circumstances in terms of their sense of subjective well-being, including feelings of depression. While intriguing results have been observed, the range of environmental events and circumstances that have been investigated has been relatively narrow. A major goal of this research was to understand how different kinds of environmental experience may—or may not—be modified by genes. Culture was a particular focus of this research. While culture has long been thought to directly influence a person’s sense of well-being, measuring culture and its influence has been difficult. This research focused on a specific facet of culture: cultural consonance. Cultural consonance measures how successful people are in achieving the broad goals that are collectively valued in their society, especially goals across the life-span (for example, creating a satisfying family life). This study builds on previous research in Brazil in which a valid model for understanding and measuring cultural consonance was developed. In the current project, the influence of cultural consonance on subjective well-being was examined to determine the extent to which that association might be modified by genetics, and to examine the association of cultural consonance with subjective well-being relative to other factors known to influence well-being, especially in interaction with genetic background. The project focused on two genetic polymorphisms thought to influence well-being. One, brain-derived neurotrophic factor, affects the health and development of nerve cells. The other, a receptor for the neurotransmitter serotonin, is related to the transmission of nerve impulses in the brain. In addition to cultural consonance, three indicators of experience in the social environment were studied. Childhood adversity refers to stressful events in childhood, such as the death or serious illness of a parent or a history of maltreatment. Stressful life events refer to current events such as divorce, death of a spouse or child, and unemployment. Frustration tolerance is a psychological disposition in which small and large setbacks can be accepted. Data were collected in a survey of over 400 adults from diverse socioeconomic groups. Genotypes were determined from samples of cells from the cheek. Other data were collected in face-to-face interviews. Subjective well-being was measured as the number of symptoms of depression, isolation, and hopelessness the respondent had experienced in the two weeks prior to the interview. Major results were as follows: Childhood adversity was moderated by genotype, especially by the serotonin receptor gene. Persons with a specific variant for the gene were at much higher risk of reporting high levels of depressive symptoms if they had experienced childhood adversity and they had that particular genotype (see Fig. 1). The moderation of genotype by childhood adversity in relation to depressive symptoms was especially strong among persons from a low socioeconomic background (see Fig. 2). Persons with this particular variant of the serotonin receptor gene and who experienced childhood adversity also had lower frustration tolerance. There was no evidence that genotype moderated the influence of any other variable. Cultural consonance proved to be the strongest influence on subjective well-being. The risk of reporting high levels of depressive symptoms was strongest for people who had low levels of cultural consonance (see Fig. 3). The results of this research present a more nuanced view of the influence of genes, the environment, and the interaction of genes and environment on subjective well-being. Persons who experience high levels of adversity in childhood are more likely to experience lower levels of well-being as adults, especially if they have a particular genetic background; on the other hand, if those individuals are able to achieve the kinds of goals in life that are widely valued in their society, they are much less likely to experience depression, isolation, and hopelessness as adults, nor does their genetic background alter the experience of cultural consonance. Subjective well-being has been shown to have a powerful influence on physical health and social and economic productivity over the life-span. This well-being matters to individuals and to society. The influences on that well-being are complex, ranging from the molecular biology of individual genetic differences to the collective goals and values called culture that help to hold a society together. Understanding and enhancing well-being for individuals and society depends on the analysis of these diverse influences, and this research contributes to that end.
