The Willpower Gene

Does DNA shape the ability to save money?

Andrey Burmakin/Shutterstock/The Atlantic

When I was a kid, my parents gave me $9 in allowance every week: $3 for savings, $3 for charity, and $3 for whatever my seven-year-old self wanted. Come Saturday, my usual payday, I’d heed the savings and charity guidelines, and then I’d go out and blow the rest on Pokémon cards.

Somewhere in the user’s manual I imagine is sent out to every new American parent when a child arrives, it must say that financial prudence can, like any other habit, be learned—truisms like “A penny saved is a penny earned” have shaped the way we think about raising responsible children. A forthcoming paper, however, suggests that my parents—bless them—might’ve been trying to teach something that can’t be taught.

The paper, which will be published next February in the Journal of Political Economy, suggests that some people are genetically predisposed to put money into savings. As pensions decay and the burden of saving shifts from employers and the government to individuals, it’s important to think about what might prevent someone from putting away money for the future. Yes, as authors Henrik Cronqvist and Stephan Siegel note, your socioeconomic status matters, but they estimate that 39 percent of the variance in how much money you have when you retire can be attributed to genetics—which might be connected to some self-control-moderating genes that influence smoking and eating habits.

Cronqvist and Siegel arrived at this conclusion after analyzing the tax filings of nearly 15,000 pairs of twins, pulling data from Sweden’s twin registry, the largest database of its kind. Their approach was clever: keeping in mind that identical twins share 100 percent of their DNA, while fraternal twins tend to share only about half, the researchers looked into the similarity in savings behavior between identical twins, and then compared it to the similarity between fraternal twins. They found that identical twins were more similar in their savings habits than their fraternal counterparts—which suggests a genetic component to savings. (The trends they observed were significant—similarities were about twice as strong in identical twins as in fraternal twins—but it should always be noted that academics disagree about the usefulness of twin-based studies.)

This isn’t to say that parents’ efforts are entirely in vain. Childhood teachings tend to induce savings into the twenties, but as people get older—and reach ages when they’re earning enough money to substantially add to savings—the influence of those teachings takes on a half-life. By the time you hit retirement, this research suggests, what your parents taught you about money doesn’t matter at all.

The Influence of Parents' Lessons on Savings,  Over Time
Cronqvist and Siegel

Joelle Saad-Lessler, an economist at the New School who has written about retirement savings, says that the role of genetics should inform the way we think about 401(k)s. “Instead of blaming people for not saving enough, this paper…shifts the discussion toward one of changing the system to make it less reliant on individual savings initiative, and more on mandated savings,” she wrote to me in an email. Financial-education programs, Saad-Lessler says, have limited potential if some people are simply predisposed to save more than others.

But Karen Richman, a cultural anthropologist at Notre Dame who has co-authored a paper with Saad-Lessler, tends to disagree, raising questions about any study that ties biology to financial behavior. Richman argues that science has a history of relying too heavily on genetic explanations, pointing to 19th-century studies on race, gender, and intelligence, whose results were used to justify a terribly unfair social hierarchy. Genetics, in other words, are beside the point, Richman says, when nearly half of American workers have no retirement savings at all. “Instead of conducting research that demonstrates the failure of the retirement savings structure—research that would provide a strong rationale for revising our financial savings policies—this study indirectly suggests that peoples’ savings rates are innate,” she said.

“If you accept that an innate, or genetic predisposition to risk or to risk-aversion can explain individuals’ financial savings behavior,” Richman added, “then the fiction that financial security or wealth depends solely on genetic predisposition can be maintained.”