More Friends, More Liberal?

Photo source.

As you prepare for your New Year's celebration, here's something to consider: researchers have found that having more friends may play a role in whether you identify yourself as a liberal or a conservative.

How did they determine this?

The researchers studied a group of about 2,000 adolescents with different variants of the dopamine receptor ("allele 7R"). The dopamine receptors in our brain are associated with pleasure, cognition, memory, learning and fine motor control to name a few key functions, and the "allele 7R" has been linked to "novelty seeking behavior." They wanted to test whether having this gene is an indicator of how one self identifies with a given ideology.

The work from groups at Harvard University and University of California at San Diego was published in The Journal of Politics {you can access the paper at this link} in October and was discussed in some news media outlets such as The Washington Post, citing:

The researchers speculate that having that the gene may make people more interested in seeking out new experiences, including learning about the points of views of their friends, exposing them to a "wider diversity of viewpoints" and leading to their liberalism.

The news media described their speculation. I wanted to take a look at the data, summarized in this Figure:

Seems pretty clear, right? To quote from their study {my emphasis added}:

Holding all else constant, for people who have two copies of the allele, an increase in number of friendships from zero to ten friends is associated with increasing ideology in the liberal direction by about 40% of a category on our five-category scale. In other words, 10 friends can move a person with two copies of the 7R allele almost halfway from being conservative to moderate or from being moderate to liberal.

I wonder whether the distribution of these alleles in the US tracks with political maps? I wonder how many alleles I have, not to mention my friends and family. Perhaps that is a question for another day. Regardless, you may want to count your friends.