Torch, Fall/Winter 2007

your cookies will be ruined.) Notice that every ingredient is important to the cookies, but the cookie is more than just flour or sugar or baking soda. There is no way to bake cookies with just one ingredient. In the same way, it is naïve (and can be cruel) to explain homosexuality as the result of just genes, or just choice, or just abuse, or just any other single cause. Many variables combine to make us who we are. Some play a larger role and some play a lesser role, but they all interact together. The developmental sequence is very important, too. A traumatic event, like being sexually abused or losing a mother, may affect us differently at age 3 than at age 11. We need a careful integrative approach that avoids oversimplification. Furthermore, two persons may arrive at the same destination by different routes. We call this the law of “equifinality.” Two people may each have identical IQs of 68, but one’s IQ may be due to Down syndrome and the other’s due to severe neglect and deprivation in childhood. Likewise, two persons may each be homosexually oriented but for quite different reasons. Once again, we must avoid the mistakes of oversimplifying and stereotyping. Not all homosexually oriented persons have a domineering mother and emotionally distant father. Not all of those homosexually oriented were sexually abused as children. We must avoid broad, sweeping generalizations that presume all of those struggling with homosexual orientation are the same. ConsideringPotential Contributors Now that we have developed a framework for evaluating the causes of homosexuality, let’s look at a list of potential contributors. Interestingly, the research evidence is not overwhelming for any of these factors. For some, the research evidence is actually very weak. Nonetheless, we present them all with the understanding that in an equation, some may play a rather small role while others are much more significant, and any number of the factors could be included in the equation. Biological Possible biological contributors to homosexuality fall into three categories — genetics, prenatal influences, and brain structures. Some studies have suggested that genetic factors may be involved in homosexuality because concordance rates (the presence of the same trait in both members of a pair of twins) for homosexuality are usually somewhat higher in identical (monozygous) twins than fraternal (dyzygous) twins. The overall concordance rates are low, however. If genes are involved, they explain a small amount of the variance, well less than half. Prenatal influences may be the most fascinating theory of biological predispositions to homosexuality. Evidence from a variety of studies suggests that exposure to abnormal hormone levels in the womb may predispose children toward homosexuality. Elevated estrogen levels, androgen levels, H-Y antigens, stress hormones, and temperament have been suspected to be linked to subsequent homosexuality. Fingerprints, finger length ratio, handedness, and bone lengths have also sometimes been linked to homosexuality. Based on animal studies, we know that the level of hormones in utero and in early development substantially influences animal sexual behavior in adulthood. One other biological explanation that has received a lot of press, but not much substantial scientific support, is brain structure. Some studies have suggested that various parts of the brain (interstitial nucleus 1–4, anterior commissure, and suprachiasmic nucleus) differ in the homosexually Fall–Winter 2007 15