Understanding the biology of homosexuality
by Margret Kopala

Published in the Ottawa Citizen, July 16, 2005

When the House of Commons redefined marriage to include homosexual unions, Prime Minister Paul Martin declared an end to the debate while in Alberta, Premier Ralph Klein mused about leaving the marriage field altogether. Since provinces have jurisdiction over solemnizing marriage, Mr. Klein's government could have authorized civil unions for all couples, leaving churches free to perform marriages as they see fit.

He has backed off this stance, but the idea of civil unions is a welcome part of a debate that has so far been monopolized by fundamentalist equality and religious arguments. Not that these aren't important but they hardly present a complete picture of the issue.

To date, even elementary facts around the biology of homosexuality and the potential effects of homosexual marriage on society have received scant attention in the mainstream press or Parliament, despite their far reaching implications.

On the scientific front, for instance, recent discoveries should put everyone in a reflective, wait-a-minute mood. To no one's surprise, these suggest that in the two to four per cent of populations that is homosexual, at least some behaviour is biologically based.

According to scientists at Oregon State University studying the breeding productivity of sheep, research on the brains of gay rams confirms the 1991 findings of neuroanatomist Simon LeVay, who discovered that the hypothalamus region of the brains of AIDS-stricken homosexual males was smaller than those of heterosexual males. "The study that we've done is an important cross-species comparison and confirms (the LeVay) results in humans," Charles Roselli, professor of physiology and pharmacology at Oregon Health and Science University told ScienCentral.com.

The research also suggests the smaller, homosexual hypothalamus is the result of hormonal fluctuations occurring at the gestational point when sexual orientation is determined.

In other research, a genetic factor was long ago suggested by work with identical and non-identical gay twins while today, cutting-edge research across a number of fields is investigating why some genes express themselves but not others. Birth order (being the younger of several brothers increases chances of being homosexual) and finger-length ratios have also been studied.

On the subject of genes and hormones, a new book Born Gay: The Psychobiology of Sexual Orientation is particularly triumphalist but few scientists will say nurture isn't a factor. Gender confusion in childhood, sexual abuse by a same-sex predator as well as absent fathers, incest and early exposure to pornography are cited in many homosexual histories. Other scientists question the "innate" theory entirely. They ask, does the brain affect behaviour or vice versa?

Nonetheless, it is with the fluctuating-hormones school of thought that science has come closest to confirming that homosexuality, like heterosexuality, is an involuntary condition not subject to external factors such as upbringing even though behavioural exceptions clearly exist.

From the arbitrary homosexuality manifested in prisons and boarding schools to the political uses of lesbianism by radical feminists, biological predisposition is no prerequisite for homosexual activity. Sexual appetites have in any case been gratified in any manner of ways since prehistory. Documented extensively by Alfred Kinsey in the '50s, these hit-and-miss enactments of Mother Nature's reproductive mission continue even though monogamous marriage has long been established as the best assurance of an individual's sexual health and lineage while stabilizing the union that has the strongest genetic interest in its progeny's survival.

For biology proponents, any victory may be pyrrhic, since the same argument that validates orientation toward homosexuality may ultimately facilitate its prevention. Questions about what causes the particular set of fluctuating hormones or expression of genes that cause homosexuality await answers, but if in the same way prenatal nutritional deficiencies or stress can cause birth complications, innate homosexuality, despite its considerable history, culture and even ideology, may be the result of similar factors.

Though no scientist appears willing to say this is possible or desirable, anticipation is in the air. Oregon State, in its endocrinological study for instance, is also investigating whether the hormonal environment in sheep can be externally influenced.

Like religiously informed concerns about similar reproductive issues, equality seekers question the ethics of such biomedical research. But will this deter others from seeking a better understanding? Contrary to the declarations of the prime minister, the current sea change in social attitudes and scientific research on homosexuality means the debate has only begun.

MARGRET KOPALA’s column on western perspectives appears every other week.

To comment, please send Margret an e-mail.

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