'Worry' Genes May Prevent Risky Investments For Some

People who have a certain combination of anxiety-generating genes often worry, and that anxiety can lead to less risky investment choices, a new study shows.

Brian Knutson, associate professor of psychology at Stanford University studies how emotions influence decisions. In 2005, he and Camelia Kuhnen, a business school graduate student, mapped out the brain regions that activated in the face of a risky decision. In 2009, Kuhnen, now an associate professor of finance at Northwestern University, linked financial risk-taking to two genes that regulate the “feel-good” neurotransmitters serotonin and dopamine.

The new paper, published in the journal PLOS ONE, explains how a serotonin gene connects to real-life financial decisions. The link, they write, is a person’s level of neuroticism. Neuroticism—also called “negative affect,”—is the trait of worriers.

“They tend to always think about the downside of things, always tending to worry about what could go wrong instead of what could go right,” Kuhnen says.

The serotonin gene is called 5-HTTLPR and comes in two varieties: short and long. Everyone has two copies, or alleles, of the gene, and individual combinations of short and long alleles are called genotypes. People with two short alleles displayed more neurotic traits, as measured by an objective psychological assessment.

For the study, researchers asked 60 volunteers from the San Francisco Bay Area to divvy up $10,000 among three investment options: stocks, bonds, or cash. On average, study participants with two short 5-HTTLPR alleles kept 24 percent more of that money in cash than did the two-long-allele carriers, who put more money in stocks.

Knutson and colleagues had previously measured participants’ financial literacy, cognition, and income level, but those factors didn’t explain the variation in investment strategy. Could the gene explain the variation?

“We found that it did,” Knutson says.

Given neurotic participants’ propensity to avoid risk, Kuhnen hypothesized that they would react just as strongly to a negative outcome. In unpublished research, Kuhnen watched how participants’ brains reacted during a game in which they learned, by trial-and-error, which of two options carried greater financial risk. Short-allele carriers displayed heightened anxiety before making a decision, but reacted no differently than long-allele carriers when they saw a negative outcome.

“The difference between these people is not about how they react to outcomes,” Kuhnen says. “It’s about how, before the choice, they think about the decision. So don’t worry so much about the worst possible outcome. Take a step back. Ask yourself: ‘really, how bad would it be?’”

Not all study participants behaved exactly as their genes would predict, Knutson says, so people shouldn’t rush out to determine whether they (or their employees) have short or long 5-HTTLPR alleles. The only reason to know, is to understand how emotions affect decisions.

“You’re not a slave to your genotype,” he says. “If you understand how it’s influencing your behavior, then you have a shot at changing that behavior.”