The Genetics of Happiness

Hugh Pickens writes "Studies comparing identical twins with non-identical twins have helped to establish the heritability of many aspects of behavior. Recent work suggests that about one third of the variation in people's happiness is heritable. Jan-Emmanuel De Neve has taken the study a step further, picking a popular suspect — the gene that encodes the serotonin-transporter protein, a molecule that shuffles a brain messenger called serotonin through cell membranes — and examined how variants of the 5-HTT gene affect levels of happiness. The serotonin-transporter gene comes in two functional variants—long and short and people have two versions (known as alleles) of each gene, one from each parent. After examining genetic data from more than 2,500 participants in the National Longitudinal Study of Adolescent Health, De Neve found that people with one long allele were 8% more likely than those with none to describe themselves as very satisfied with life and those with two long alleles were 17% more likely of describing themselves as very satisfied. Interestingly enough, there is a notable variation across races with Asian Americans in the sample having on average 0.69 long genes, white Americans with 1.12, and black Americans with 1.47. 'It has long been suspected that this gene plays a role in mental health but this is the first study to show that it is instrumental in shaping our individual happiness levels (PDF),' writes De Neve. 'This finding helps to explain why we each have a unique baseline level of happiness and why some people tend to be naturally happier than others, and that's in no small part due to our individual genetic make-up.'"

Comments

Re:Will wonders never cease

[fuzzyfuzzyfungus]

Given the observed sensitivity, especially but not exclusively neonatal, to environmental influences, and the whole field of epigenetic study, it is neither obvious, nor obviously true, that our genetic make-up determines who we are.

Thanks to twin studies and other convenient test populations, we've been able to determine that some things are extremely heritable; but that others are surprisingly minimally so. There are even a number of factors(mostly metabolic and neurological stuff that is laid down in utero) where the developing embryo takes enough chemical cues from mommy that a practically Lamarkian pattern of 'inheritance' is seen.

Re:Black people happier?

[dkleinsc]

Baseline happiness can arguably be negatively correlated to competitiveness, drive and success.

Or not, because people who are depressed feel like it doesn't matter what they do, life's going to suck anyways. They may also respond to their constant unhappiness by looking for artificial mood boosters, which can lead to alcoholism or drug use. They frequently also fail to recognize the value of their accomplishments. By contrast, a happier person is more likely to trigger their brain's reward mechanisms when they do something productive, so they're likely to repeat the behavior.

And it's also worth noting that it's unclear to what degree "drive" and "competitiveness" has to do with "success": The best predictor of a person's level of educational attainment is their parents' educational attainment. The best predictor of athletic success is genetic advantages like height, eyesight, and weight. Artistic success has a fair amount to do with whether a kid's artistic efforts were encouraged or discouraged early on. Most of the really wealthy people in the US inherited a significant amount (Paul Allen is the exception on this front, not the rule).