Do genes explain Republican extreme negative campaign tactics?

Warning: Anyone who takes this post seriously please resist the temptation to comment.

Over the reported objections of John McCain and national GOP officials, North Carolina's state Republican party is about to run a campaign ad attacking Barack Obama for consorting with Jeremiah Wright. The ad disingenuously implies that Obama was sitting in the congregation when Wright made some of his more inflammatory remarks condemning America, even though there is no evidence to suggest that Obama was anywhere near the church at the time. Why are these kinds of dirty campaign tricks invariably the product of a Republican? Can science provide some insight? Perhaps.

Consider America's recent history of dirty campaign tricks.

Nixon's escapades in the Watergate Hotel.

George H.W. Bush's mendacious "Willie Horton" ad in 1988 that unfairly accused then Gov. Michael Dukakis of enabling revolving-door jail terms for convicts.

The fictional allegations leveled against John McCain in 2000 regarding an African American child born out of wed-lock.

The Swift-boating of John Kerry.

The list goes on. All were instigated by Republicans. It may be possible to dredge up a few examples of Democratic skullduggery, but I doubt that any rise to the level of the examples listed above.

My point is: why do only Republicans engage in such tactics? Does cultural transmission explain it all? Or could there be a genetic component? I wrote a few days ago about a New Scientist story on studies suggesting such an explanation for political leanings in general.

...twin studies suggest that opinions on a long list of issues, from religion in schools to nuclear power and gay rights, have a substantial genetic component. The decision to vote rather than stay at home on election day may also be linked to genes. Neuroscientists have also got in on the act, showing that liberals and conservatives have different patterns of brain activity.

If politics does run in families, could not the propensity to engage in dirty politics do the same?

Imagine that there's a gene mutation that predisposes one to right-wing politics as described the quote above. Individuals who carry the gene tend to support individualism over collective rights, personal wealth-accumulation over environmental sustainability, and so forth. In other words, a selfish gene (as opposed to Richard Dawkin's Selfish Gene, which is an entirely different idea). Does it not makes sense that a heavy dose of whatever protein is expressed by this gene would lead to extreme selfish behavior? Star Trek's Data would call such behavior a product of a malfunctioning ethical subroutine.

This country is roughly divided 40-40-20 among Republicans, Democrats and independent. Imagine then, that this gene occurs in 40 percent of the general population (P=0.4). Assume further that this gene confers no reproductive advantage. Its selection value is neutral, and therefore remains at 0.4. (This point is arguable, considering the tendency for right-wing parents to have more children, but I am trying to keep this scenario simple.)

Given these assumptions, the offspring parents who both carry the recessive gene would tend towards ethical lapses. Assuming random mating (again, an arguable assumption), such individuals would represent 16% of the population (0.4 x 0.4 = 0.16). But almost all of that 16% would be Republican. This means that the vast majority of Republicans would still be decent people, people who believe some strange stuff, but still respect the need for honesty and fair play in politics. But a significant minority would be willing to do whatever it takes to get their favored candidate elected.

Which is pretty much exactly what we see on the American political landscape. This explanation helps me deal with the current state of affairs because I don't want to hate Republicans, even the ones on the far end of the curve who are destroying the public's confidence in democracy. If it's just genes at play, then we have to sympathetic. They can't help it. It's not their fault. They were programmed that way.