Are these headline writers incompetent because of their genetics?

Article title in The Post Chronicle: Liberal Gene Discovered: Is Being Liberal Decided At Birth?

Article title at their linked source, ScienceBlog: Researchers find a ‘liberal gene’

Original article title: Friendships Moderate an Association between a Dopamine Gene Variant and Political Ideology

A choice quote from the abstract: Here, we hypothesize that individuals with a genetic predisposition toward seeking out new experiences will tend to be more liberal, but only if they are embedded in a social context that provides them with multiple points of view.

Note that they didn't discover a gene at all. They did show that, among people with a genetic variant already known to predispose people toward novelty seeking, having more friends is positively correlated with self-reported liberal ideology (and among people without the variant, there is no correlation between ideology and number of friends).