Researchers have determined that genetics could matter when it comes to some adults' political leanings.
According to scientists at UC San Diego and Harvard University, "ideology is affected not just by social factors, but also by a dopamine receptor gene called DRD4." That and how many friends you had during high school.
The study was led by UCSD's James Fowler and focused on 2,000 subjects from the National Longitudinal Study of Adolescent Health. Scientists matched the subjects' genetic information with "maps" of their social networks. According to researchers, they determined that people "with a specific variant of the DRD4 gene were more likely to be liberal as adults." However, the, subjects were only more likely to have leanings to the left if they were also socially active during adolescence.
"It is the crucial interaction of two factors -- the genetic predisposition and the environmental condition of having many friends in adolescence -- that is associated with being more liberal,” according to the study.
"These findings suggest that political affiliation is not based solely on the kind of social environment people experience,” said Fowler, who is a professor of political science and medical genetics.
The researchers also said their findings held true no matter what the ethnicity, culture, sex or age of the subjects were.