Julio and Mauricio Cabrera are gay brothers who are convinced
their sexual orientation is as deeply rooted as their Mexican
ancestry. They are among 1,000 pairs of gay brothers taking part in
the largest study to date seeking genes that may influence whether
people are gay.
The Cabreras hope the findings will help silence critics who say
homosexuality is an immoral choice.
If fresh evidence is found suggesting genes are involved,
perhaps homosexuality will be viewed as no different than other
genetic traits like height and hair color, said Julio, a student at
DePaul University in Chicago.
Adds his brother, "I think it would help a lot of folks
understand us better."
The federally funded study, led by Chicago-area researchers,
will rely on blood or saliva samples to help scientists search for
genetic clues to the origins of homosexuality. Parents and straight
brothers also are being recruited.
While initial results aren't expected until next year -- and
won't provide a final answer -- skeptics are already attacking the
methods and disputing the presumed results.
Previous studies have shown that sexual orientation tends to
cluster in families, though that doesn't prove genetics is
involved. Extended families may share similar child-rearing
practices, religion and other beliefs that could also influence
sexual orientation.
Research involving identical twins, often used to study genetics
since they share the same DNA, has had mixed results.
One widely cited study in the 1990s found that if one member of
a pair of identical twins was gay, the other had a 52 percent
chance of being gay. In contrast, the result for pairs of non-twin
brothers, was 9 percent. A 2000 study of Australian identical twins
found a much lower chance.
Dr. Alan Sanders of Evanston Northwestern Healthcare Research
Institute, the lead researcher of the new study, said he suspects
there isn't one so-called "gay gene."
It is more likely there are several genes that interact with
nongenetic factors, including psychological and social influences,
to determine sexual orientation, said Sanders, a psychiatrist.
Still, he said, "If there's one gene that makes a sizable
contribution, we have a pretty good chance" of finding it.
Many gays fear that if gay genes are identified, it could result
in discrimination, prenatal testing and even abortions to eliminate
homosexuals, said Joel Ginsberg of the Gay and Lesbian Medical
Association.
However, he added, "If we confirm that sexual orientation is an
immutable characteristic, we are much more likely to get the courts
to rule against discrimination."
There is less research on lesbians, Sanders said, although some
studies suggest that male and female sexual orientation may have
different genetic influences.
His new research is an attempt to duplicate and expand on a
study published in 1993 involving 40 pairs of gay brothers. That
hotly debated study, wrongly touted as locating "the gay gene,"
found that gay brothers shared genetic markers in a region on the X
chromosome, which men inherit from their mothers.
That implies that any genes influencing sexual orientation lie
somewhere in that region.
Previous attempts to duplicate those results failed. But Sanders
said that with so many participants, his study has a better chance
of finding the same markers and perhaps others on different
chromosomes.
If these markers appear in gay brothers but not their straight
brothers or parents, that would suggest a link to sexual
orientation. The study is designed to find genetic markers, not to
explain any genetic role in behavior.
And Sanders said even if he finds no evidence, that won't mean
genetics play no role; it may simply mean that individual genes
have a smaller effect.
Skeptics include Stanton Jones, a psychology professor and
provost at Wheaton College in Wheaton, Ill. An evangelical
Christian, Jones last month announced results of a study he
co-authored that says it's possible for gays to "convert" —
changing their sexual orientation without harm.
Jones said his results suggest biology plays only a minor role
in sexual orientation, and that researchers seeking genetic clues
generally have a pro-gay agenda that will produce biased
results.
Sanders disputed that criticism.
"We do not have a predetermined point we are trying to prove,"
he said. "We are trying to pry some of nature's secrets loose with
respect to a fundamental human trait."
Jones acknowledged that he's not a neutral observer. His study
involved 98 gays "seeking help" from Exodus International, a
Christian group that believes homosexuals can become straight
through prayer and counseling. Exodus International funded Jones'
study.
The group's president, Alan Chambers, said he is a former
homosexual who went straight and believes homosexuality is morally
wrong.
Even if research ultimately shows that genetics play a bigger role,
it "will never be something that forces people to behave in a
certain way," Chambers said. "We all have the freedom to
choose."
The Cabrera brothers grew up in Mexico in a culture where "being
gay was an embarrassment," especially for their father, said
Mauricio, 41, a car dealership employee from Olathe, Kan.
They had cousins who were gay, but Mauricio said he still felt
he had to hide his sexual orientation and he struggled with his
"double life." Julio said having an older brother who was gay made
it easier for him to accept his sexuality.
Jim Larkin, 54, a gay journalist in Flint, Mich., said the
genetics study is a move in the right direction.
Given the difficulties of being gay in a predominantly straight
society, homosexuality "is not a choice someone would make in
life," said Larkin, who is not a study participant.
He had two brothers who were gay. One died from AIDS; the other
committed suicide. Larkin said he didn't come out until he was
26.
"I fought and I prayed and I went to Mass and I said the
rosary," Larkin said. "I moved away from everybody I knew ...
thinking maybe this will cause the feelings to subside. It
doesn't."
(Agencies via China Daily October 16, 2007)