THE MOLECULE OF MORE
you grew up in, and whether you were encouraged to be
creative at a young age, to name a few. Having one specific
gene usually has only a small effect. So while these studies
advance our understanding of how the brain works, they’re
not very good at predicting how a particular individual—one
member of that large group—will behave. In other words,
some observations about a group you belong to may not be
true about you in particular. That’s to be expected.
RECEPTOR GENES AND THE LIBERAL–
CONSERVATIVE SPLIT
There’s a good chance that the difficulty the conservatives faced
stemmed from differences in their DNA. In fact, political attitudes in
general seem to be influenced by genetics. In addition to the American
Journal of Political Science article just discussed, other studies support a
link between a genetic disposition to a dopaminergic personality and
a liberal ideology. Researchers from the University of California, San
Diego focused on a gene that codes for one of the dopamine receptors
called D4. Like most genes, the D4 gene has a number of variants.
Slight variations in genes are called alleles. Each person’s collection of
different alleles (along with the environment they grew up in) helps
determine their unique personality.
One of the variants of the D4 gene is called 7R. People who have
the 7R variant tend to be novelty-seeking. They have less tolerance for
monotony and pursue whatever is new or unusual. They can be impul-
sive, exploratory, fickle, excitable, quick-tempered, and extravagant. On
the other hand, people with low novelty-seeking personalities are more
likely to be reflective, rigid, loyal, stoic, slow-tempered, and frugal.
The researchers found a connection between the 7R allele and
adherence to liberal ideology, but only if a person grew up around peo-
ple with a variety of political opinions. There had to be both a genetic