When a Columbia University psychiatrist announced last week that he had proof that some gays can turn straight, the news raised more than a few eyebrows among experts who have been studying the origins of sexual orientation.

While science has been unable to establish a definitive biological basis for homosexuality, most experts believe it at least plays a role. Moreover, they dismiss as psychologically damaging efforts at converting people from gay to straight.

Dr. Robert Spitzer's study was based on a telephone survey of 200 gay men and lesbians who claim to have achieved a change to heterosexual attraction that has lasted at least five years.

He found that for the year leading up to the interview, 66 percent of the men and 44 percent of the women achieved "good heterosexual functioning" -- meaning they had had physically satisfying sex at least monthly with their heterosexual partners, never or rarely thinking of homosexual sex during intercourse.

The limited sampling was troublesome to other experts, who criticized the study as lacking in scientific rigor. They noted there was no control group, no physiological testing or evidence of long-term success.

Also, many in the Spitzer study came from religious groups that consider homosexuality a curable disorder, which concerns such experts as Dr. William Byne, a neuroanatomist and psychiatrist at Mount Sinai School of Medicine in New York.

"You'd have to follow the people for a more extended period of time and have 100 percent confidence in what they are telling you," said Byne, who is researching brain differences between gays and straights. "Frankly, you need to know more about their motives. There must have been tremendous internalized homophobia as well as tremendous external pressure for them to convert."

Because a person can be made to do something they normally wouldn't do, such as have a heterosexual relationship, that doesn't mean they changed their orientation, Byne said.

"It doesn't surprise me at all that highly motivated (gays) could possibly achieve heterosexual functioning," Byne said. "I'd be more surprised if their homosexual inclinations were eliminated."

Since releasing his study last week, Spitzer said he's been bombarded by hate mail from people who claim it is fomenting homophobia and harassment.

He spoke of a law student, a lesbian, who, Spitzer said, was followed by classmates who advised her to get therapy to change her sexual orientation.

"That's awful, and it wasn't the intention of the study," Spitzer said. "We underscored that homosexuality should not be construed as a question of choice,

nor does the study say that any homosexual change if (he or she) wanted to.

"My mission was to answer a scientific question: How fluid is sexual orientation? Can someone who is deeply conflicted change their behavior, their attraction? The answer is: probably a small group with varying degrees of success."

The information also conflicted with another study -- also presented last week at the American Psychiatric Association's annual meeting -- which found that of 202 gay and lesbian subjects who had sought therapy to overcome their homosexual feelings, 178 reported their efforts had failed.

Scientists who have established a direct link between biology and homosexuality find the Spitzer study highly problematic.

For example, S. Marc Breedlove, a University of California at Berkeley psychologist, reported last year that differences in finger lengths showed a prenatal basis for sexual orientation. Of 720 people surveyed, lesbians on average had a more masculine finger length pattern than heterosexual women. The data, Breedlove concluded, showed some lesbians were exposed to more fetal androgen than heterosexual women.

Another researcher, Dr. Ray Blanchard, head of the Clinical Sexology Program at the Centre for Addiction and Mental Health in Toronto, found a tendency toward left-handedness in gay subjects. He said Spitzer's study offers "zero proof" people's sexual preferences can be changed.

"People over the centuries have been able to repress their natural sexual impulses," Blanchard said. "Look at priests and nuns . . . and prison inmates who, absent the company of women, have sex with each other."

Some studies also suggest differences have been found in the inner ear of heterosexual and lesbian women.

Ironically, Spitzer spearheaded the effort in 1973 to remove homosexuality from the list of mental disorders in the psychiatric association's diagnostic manual.

"I may be the moth drawn to a flame," Spitzer said in explaining his transformation since 1973. "I get attracted to challenging orthodoxy. Before 1973, the conventional wisdom was: 'There must be something with you wrong because you're gay.' Now, in 2001, it's, 'If you're homosexual, you're born that way.' The bottom line is: Can you respect someone with diminished homosexual impulses, is that a legitimate goal?"

Simon LeVay, whose published research in 1991 suggests differences in the brains of gays, dismissed Spitzer's study.

"This (reparative therapy) is a dying business," he said. "In the 1960s, gays by the thousands were seeking psychotherapy to change. Now, most people understand being gay can be as rewarding a life as being heterosexual."

Sexual orientation
Reasons for wanting to change sexual orientation
Gay lifestyle not emotionally satisfying: 81%
Religious conflict: 79%
Desire to get or stay married 
 Men:   67%
 Women: 35%
Indicators of sexual orientation, before and after the change
At least a few times a month, looking with lust at the same sex or daydreaming 
about having sex with a same-sex partner: 
-- Before
 Men: 99% 
 Women: 87% 
-- After
 Men: 30% 
 Women: 5% 
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