The next time you lose a bet, you may be able to blame your genes.
Researchers in Singapore and the United States have linked five genes to people's behaviour when it comes to betting.
The genes are all involved in regulating dopamine, a chemical released in the brain that signals pleasure and motivates people to seek rewards.
The scientists said their work showed how people have hardwired biases when they think about strategies and make decisions.
"If you think of the brain as a computing machine, there are areas that take inputs, crank them through an algorithm and translate them into behavioural outputs," said Ming Hsu from the University of California, Berkeley.
The researchers used MRI imaging to study the brains of about 220 Han Chinese students at the National University of Singapore (NUS) while they bet against an anonymous competitor via a computer.
An almost-complete genetic profile of each student had been compiled in a database as part of a larger project, involving more than 3,000 students, to look into human decision-making.
"We know from brain-imaging studies that when people compete against one another, they actually engage in two distinct types of learning processes," said Eric Set, a graduate student from the University of Illinois at Urbana-Champaign.
The study found that variations in three genes determined how well students were able to imagine what their competitors were thinking and respond accordingly - a process known as "belief learning".
Differences in the other two genes affected how quickly the students forgot past experiences and changed strategies - called trial-and-error "reinforcement learning".
Chew Soo Hong from NUS' Department of Economics said the study's findings showed how the different dopamine genes contribute to an individual's thinking in a "winner-takes-all competitive game".
The hardwired biases could have an impact on business decisions, the researchers said.
Their work was published on Monday in the online edition of the US Proceedings Of The National Academy Of Sciences.
It was funded by Singapore's Ministry of Education, the National Institute of Mental Health in the US and French insurance giant AXA Group's AXA Research Fund.
This article by The Straits Times was published in MyPaper, a free, bilingual newspaper published by Singapore Press Holdings.
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