Sherry Chisamore is convinced she doesn’t have an investing bone in her body. Sure she’s tried. Stock tips. Investing for Dummies. The Wealthy Barber. She’s not even comfortable being a passive index investor. Chisamore is at a loss to explain why. After all, she always had As in school, she has biology and physiotherapy degrees, and she has a successful career as a physiotherapist. More than that, she’s good with numbers; in fact she oversees the books at her practice.

Is it possible that investing just isn’t in her DNA? A growing body of research indicates that could indeed be the case—because a person’s genes actually do correlate with their investing personality.

One of the most recent studies comes from a trio of researchers at Claremont McKenna College near Los Angeles and the University of Washington in Seattle. After studying the financial portfolios of more than 38,000 identical and fraternal twins, they concluded that genetics can explain about one-third of their investment behaviour. Remarkably, the study found twins who grew up in different environments still exhibited similar approaches to investing, right down to their asset allocations and how active they are in the markets.

Genes do matter, says Steph­an Siegel, an associate professor at the University of Washington’s Foster School of Business and co-author of the study. In some ways, they’re more important than upbringing. “The parents’ investing behaviour doesn’t have a lasting effect on their children’s investing behaviour,” he says.

But Siegel’s study doesn’t look at which genes actually make you a good or bad investor. To get a better sense of that, you have to unwind the chromosome. Take the monoamine oxidase A, or MAOA, gene for example. Researchers at the London School of Economics and the University of California, San Diego, say variations in this speck of amino acid can determine the likelihood that you’ll rack up debt. People with both “debtor gene” variations are 16% more likely to carry a balance on their credit card.

Even financial risk can be decoded. A joint study by Northwestern University’s Kellogg School of Management and the school’s Interdepartmental Neuroscience program found that a pair of genes that regulate dopamine and serotonin in men control their risk-taking behaviour. They found that those with particular alleles of these genes may take as much as 25% more risk than individuals without.

Still, you may want to hold off getting your DNA mapped before your next big investment decision. Siegel says genes are important, but they aren’t the only factor. “A big part of their decisions are still based on things people learned throughout their lives.”