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What science tells us about same-sex unions


Our immune system, certainly one of the great marvels of nature, equips us with 100 billion (100,000,000,000) immunological receptors.

The T cell (blue), one of the immune system's principle means of defense.

Each of these tiny receptors has the uncanny natural capacity to distinguish the self from the non-self. Consequently, they are able to immunize or protect our bodies against the invasion of foreign substances that could be harmful to us.

Marvelous as nature is, it is never extremist. From a purely immunological point of view (from the standpoint of an all-out defensive strategy), a woman's body would reject the oncoming sperm, recognizing it as a foreign substance. But this is precisely the point at which nature, we might say, becomes wise. If our immune system regards sperm as a potential enemy, then fertilization would never take place, and the human race would have come to an early demise with the passing of Adam and Eve.

But something extraordinary occurs, which makes fertilization and the continuation of the human race possible. Traveling alongside the sperm in the male's seminal fluid is a mild immunosuppressant. Immunologists refer to it as consisting of "immunoregulatory macromolecules." This immunosuppressant is a chemical signal to the woman's body that allows it to recognize the sperm not as a non-self, but as part of its self. It makes possible, despite the immune system's usual preoccupation with building an airtight defence system, a "two-in-one-flesh" intimacy.

We have noted two important features about the content of male semen: 1) the capacity of the sperm to fuse with the nucleus of the woman's egg (fertilization); and 2) the mild immunosupressant that allows the woman's immune system to welcome the male sperm as part of her own flesh.

Now that sodomy is talked about as a human right to be exercised by male same-sex couples without discrimination, we may ask the pertinent question: what happens when sperm is deposited in the rectal area rather than in the vaginal area?

Male sperm, being blissfully unresponsive to political ideologies or cultural trends, go right ahead and behave strictly according to their nature. They penetrate the nucleus of whatever body cell (somatic cell) they might encounter. This fusing, however, does not result in fertilization, the first stage in the life of a new human being, but, as scientists have shown, can and does result in the development of cancerous malignancies. In an article entitled, "Sexual Behaviour and Increased Anal Cancer," published in Immunology and Cell Biology, authors Richard J. Ablin and Rachel Stein-Werblowsky, report that "anal intercourse is one of the primary factors in the development of cancer." According to the prestigious New England Journal of Medicine, "Our study lends strong support to the hypothesis that homosexual behaviour in men increases the risk of anal cancer." In addition, the International Journal of Cancer finds that, "Being single and having practised anal intercourse appears to be associated with anal cancer and case reports have suggested a recent increase in the number of cases of anal cancer." The medical references are legion.

Also, we may ask: what happens when the male immunosuppressant is deposited in the rectal area? Scientists tell us that when this occurs, an "immunopermissive environment" is created.

This environment, in which the immune system is not working as it should, is favourable for the perpetration of spermatozoa-induced tumors and other pathologies. It is as if, in this instance, the immune system becomes confused and welcomes its enemies. C. Rabkin et al., in the American Journal of Epidemiology, found a decreasing immunocompetence in a substantial proportion of HIV-positive homosexual men, particularly those with a history of intraepithelial abnormalities.

Depositing sperm in the "wrong place" (like pouring motor oil into the gas line), by nature's standards, is courting disaster. Nature, we might add, demands respect. It does not make accommodations to politically based ideologies or individual preferences. From nature's standpoint, there is no equality between heterosexual and male homosexual intercourse.

Furthermore, the vagina is totally impermeable to viruses. By contrast, the rectum is designed to absorb up to the last possible useful nutrient that we have eaten. There is an enormous lymphatic network (involving blood vessels) in the lining or mucosa of the rectum. Therefore, the rectal area is designed to absorb, and will absorb, the ingredients of male semen if they are in the vicinity.

The same-sex issue is hotly contested. This is par for the course when it comes to moral issues.

All too often, as it is commonly said, there is far more heat than light. In order to bring some measure of objectivity to the discussion, a close observation of nature, such as science can provide, is extremely helpful. Science, like nature, is immune to political or fashionable trends. But in looking closely and carefully at what the science of immunology can tell us, we have even more reason for upholding and honouring the wisdom of marriage as a union of a man and a woman. And what is more, we have added reason to feel awe when we re-read the first chapter of Genesis, which refers to marriage as a union of "two in one flesh."


Donald DeMarco. "What science tells us about same-sex unions." The Interim (April, 2004).

This article reprinted with permission from The Interim.


Donald DeMarco is Professor at Holy Apostles College and Seminary in Cromwell, CT and Professor Emeritus at St. Jerome's University in Waterloo Ontario. He has written hundreds of articles for various scholarly and popular journals, and is the author of twenty books, including The Heart of Virtue, The Many Faces of Virtue, Virtue's Alphabet: From Amiability to Zeal and Architects Of The Culture Of Death. Donald DeMarco is on the Advisory Board of The Catholic Educator's Resource Center.

Copyright 2004 The Interim



Copyright 2004 Victor Claveau. All Rights Reserved