WASHINGTON -- After promoting his fondness for Lady Gaga songs, former Minnesota Gov. Tim Pawlenty was asked over the weekend whether he thinks gays were "Born This Way," the title of Gaga's latest hit. Pawlenty's response? "The science ... is in dispute."

On that point, scientists say Pawlenty is on partially solid ground. Although few scientists believe that homosexuality is a lifestyle choice -- as many social conservatives believe -- there's also no consensus as to how much sexual orientation is determined by genetic, hormonal or environmental factors.

More importantly for Pawlenty is what the question means to his presidential prospects in Iowa, where social conservatives are still smarting about a 2009 state Supreme Court ruling legalizing gay marriage. The decision made Iowa the third state -- and the first in the nation's heartland -- to do so.

Both Pawlenty and Minnesota Republican Michele Bachmann have been playing to the state's influential Christian conservatives, who succeeded last fall in ousting three of the judges involved in that decision.

"This is still a lingering and potent issue with Iowa caucusgoers," said Tim Albrecht, an aide to Gov. Terry Branstad, who remains neutral in the battle for the GOP nomination in the 2012 presidential race.

On the stump and in television ads, Pawlenty frequently reminds Iowans of his conservative judicial appointments as governor of Minnesota.

'Marriage vow'

Bachmann, meanwhile, signed on last week to a "marriage vow" committing candidates to stand against same-sex marriage, as well as against an "anti-scientific bias which holds, in complete absence of empirical proof, that non-heterosexual inclinations are genetically determined, irresistible and akin to innate traits like race, gender and eye color."

The pledge is being promoted by the Family Leader, a group led by Bob Vander Plaats, former state chair for Mike Huckabee's 2008 presidential campaign.

Plaats, sometimes described as a kingmaker in Iowa Republican politics, has suggested that the pledge will be a condition for his group's support.

Whether Pawlenty signs on remains to be seen. A spokesman for his campaign said Monday that Pawlenty is "in the process of reviewing the pledge."

Over the weekend, the group retracted a controversial part of the pledge that seemed to suggest that slave families in the South had stronger family structures than black families today. Bachmann also disavowed that part of the pledge, but she remains the only major GOP candidate to sign on.

Among the leading contenders in an influential straw poll in Iowa next month, Bachmann and Pawlenty have both staked out strong positions against same-sex marriage and other types of legal rights. Both support a constitutional amendment forbidding gay marriage in Minnesota. Both have been "glitter-bombed" by gay activists.

Although Pawlenty once voted to extend civil rights to gays and lesbians as a member of the Minnesota Legislature, he has since expressed regret for the vote.

As a presidential candidate, he has backed the Pentagon's "Don't Ask Don't Tell" prohibition on gays in the military.

A choice?

Now, with a growing debate in Iowa about the marriage pledge, Pawlenty was asked Sunday during an appearance on "Meet the Press" whether he believes being gay is a choice, or whether, as Lady Gaga says, gays are "born this way."

"Well, the science in that regard is in dispute," Pawlenty said.

Pressed, Pawlenty wavered on whether being gay is a choice, but clarified that "there's no scientific conclusion that it's genetic."

Eli Coleman, of the University of Minnesota's program on human sexuality, said that Pawlenty is right, as far as that goes. "The only nuance is that we haven't disproved it," said Coleman.

The scientific question, Coleman said, is the extent to which genetics plays a part. "Mainly, it's a complex of genetic, hormonal, and environmental influences," he said. "It's a complex of the interplay between these factors. But it's really not a choice."

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.


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