The fact that the people of Ghana, Nigeria, Mexico, Venezuela and Colombia mostly respond to the question “Are you happy?” with “Very happy” has nothing to do with the number of hours of sunshine in the countries where they live, nor with their purchasing power. An international team of scientists has found an explanation to the world rankings of the subjective perception of happiness in our DNA.
An analysis of the responses from more than 65 countries to the World Values Survey, which annually polls the beliefs, values and motivations of people around the globe, has brought to light a variant of a gene directly related to the feeling of happiness. Specifically, the title “the gen of happiness” would correspond nicely to allele A of the fatty acid amide hydrolase. This variant form of a gene slows the chemical degradation of anandamide, an endogenous cannabinoid that increases pleasurable sensations and reduces the perception of pain.
Those nations with more prevalence of this allele, mainly located in South America or West Africa, are the ones that declared themselves happier. At the opposite end of the pole are the citizens of Iraq, Jordan, Hong Kong, China, Thailand and Taiwan, with lower prevalence of this allele and who considered themselves less happy. This genetic difference also explains why northern Europeans, and especially the Swedes, declare themselves to be happier than their neighbors in southern and central Europe.
However, it doesn’t necessarily follow from here that we have to rule out any relationship between climate and happiness. In fact, it doesn’t seem to be by chance that allele A is more common in tropical and equatorial areas of America and Africa. “Everything points to natural selection in the tropical environment favoring allele A, possibly to counteract the environmental stressors to which those who live in this part of the world are exposed,” concludes Michael Minkov, co-author of the study, who goes on to say that genetics can influence, but not prevent, other factors such as the welfare state or military conflicts from increasing or decreasing such ratios in a population.
The smiley gene
Do you consider yourself a person who laughs easily? Do you usually roar with laughter when you hear a good joke? Are you the first one to crack up when something hilarious happens? Your genes may have much to do with it, according to a recent study by Northwestern University (USA) and the University of Geneva (Switzerland). Positive emotional expressions, such as smiling and laughter, are more common in people who have short alleles for gene 5-HTTLPR, according to the study. This gene is involved in the regulation of serotonin, the neurotransmitter of happiness.
However, these same variants of the gene have also been shown to be associated with increased sensitivity to negative emotions, and may even predispose one to depression. Why might this be? Claudia M. Haase, who led the study, told OpenMind that “having short allele is not bad. It simply amplifies all emotional reactions, both positive and negative.” In her experiments she has shown that this means that these people laugh more during a funny movie. And in everyday life, “a person with short alleles for gene 5-HTTLPR will be extremely happy in a positive environment and suffer greatly in emotionally unfavorable situations,” says Haase, who adds that this is another clear example that genes “modulate”, but don’t have the last word.
The inheritance of happiness
The influence between happiness and genes is reciprocal. In the same way that certain DNA sequences push us to be happy, a positive mood affects the expression of genes, according to a study by the University of California, Los Angeles (USA), reprinted in the magazine PNAS. The authors found that the genetics of immune cells is more favorable in subjects with high levels of what is known as eudaimonic wellbeing, which is the kind of happiness that comes from having a purpose in life, growing, striving to achieve goals and develop ones own skills.
Specifically, this wellbeing is associated with a reduction in inflammatory gene expression and strong gene activity related to the activity of antibodies and the natural defense against viruses and pathogenic bacteria. This contrasts with the health effects of purely hedonistic pleasure, which emphasizes the pleasurable sensations and the absence of pain, and which, according to research, causes the opposite effect on the immune system.
Delving a little more deeply, some researchers even suggest that happiness not only modifies the genome itself, but also that of one’s offspring. When we laugh we generate endorphins and other brain chemicals that are capable of producing changes in our reproductive cells: sperm and ovum. If this hypothesis is proved correct, we could be inheriting, at least in part, the much sought-after happiness.