Political and Economic Choices Determined Biologically
Photo of protesters at the Capitol in Washington, DC on 9/12/09. The Tea Party gathering was in protest of Obama's healthcare plan and government spending.
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Financial risk and attitudes toward environmental policy are important factors that determine if someone leans right or left politically. A large genetic survey has indicated these political and economic decisions can be linked to a range of genetic factors.

The researchers studied the genetic data and economic and political preferences of about 3,000 subjects. The results of this analysis were published May 7 in the journal Proceedings of the National Academy of Sciences.

The study showed that unrelated people who happen to be more similar genetically also have more similar attitudes and preferences in the political and economic realm. This finding suggests that genetic data — taken as a whole — could eventually be moderately predictive of economic and political preferences.

This isn't to say that one gene makes someone a republican, but when the entire genome and one's entire suite of opinions is taken together, there is a definite trend, study researcher Daniel Benjamin, of Cornell University, said.

The study also found evidence that the effects of individual genetic variants are tiny, and these variants are scattered across the genome. Given what is currently known, the molecular genetic data isn't strong enough to predict any person's feelings on the 10 traits studied, though, which included preferences toward environmental policy, foreign affairs, financial risk and economic fairness.

This conclusion is at odds with dozens of previous papers that have reported large genetic associations with such traits, but the present study included ten times more participants than the previous studies.

"An implication of our findings is that most published associations with political and economic outcomes are probably false positives," Benjamin said in a statement. "These studies are implicitly based on the incorrect assumption that there are common genetic variants with large effects."

The research team concluded that it may be more productive in future research to focus on behaviors that are more closely linked to specific biological systems, such as nicotine addiction, obesity, and emotional reactivity, and are therefore likely to have stronger associations with specific genetic variants.

"If you want to find genetic variants that account for some of the differences between people in their economic and political behavior, you need samples an order of magnitude larger than those presently used," Benjamin said.