Jon Green throws the SPOTLIGHT on genetic influences in the formulation of people’s political attitudes:
It would be silly to think of newborn babies’ brains as being a blank slate. The preponderance of biological research has shown that differences in our genes play a large role in our personality. But certainly our political opinions are formed some time after we’re born, since we need some actual political information before we can develop political attitudes, right?
Numerous studies have shown that monozygotic (identical) twins are more likely than dizygotic (fraternal) twins to hold similar political opinions and exhibit similar political behaviors, showing that our genes play a role in determining what our political opinions are, how strongly we hold them and even whether or not we decide to vote.
What’s important to note, as is the case with all twin studies, is that comparing identical to fraternal twins controls for the “shared household” objection. It’s natural to assume that twins, or siblings, will share political attitudes because they grow up in the same house in the same geographic area with the same parents telling them what to think. But when identical twins, with matching genes, are more alike than fraternal twins, who only share 50% of each others’ genes, the difference between the two can be attributed to genetic difference.
So, while this is not to say that our political opinions are 100% set when we’re born, nature provides a robust “first draft,” or cognitive structure, which we use to process information and which helps construct our political attitudes as we mature. It is perhaps for this reason that studies examining this phenomenon have consistently found that genes play a significant role in the ideologies we hold, but not the parties we identify with. The former is internal and value-based; the latter is an external and artificial construction – far more prone to environmental manipulation.